12. Explain why is (+5) + (-7) = -2.
Answers
Let's use a number line to help us visualize what's going on.
Starting at 0, +5 takes us 5 units to the right.
From there, -7 moves us 7 units back to the left and we end up at -2.
So (+5) + (-7) simplifies to -2.
Take a look at the image below.
Related Questions
32.
What is the value of x for ∆DEF?
HELP! Answer if you can!!
Answers
Step-by-step explanation:
[tex]c^{2} = {a}^{2} + { b}^{2} [/tex]
Pythagoras theorem
x²=12² + 5²
x²=144+25
x²=169
[tex]x = \sqrt{169} [/tex]
x=13
Answer:
x = 13
Step-by-step explanation:
Using the Pythagorean Theorem to find the missing hypotenuse side:
[tex]a^2+b^2=c^2[/tex]
12 and 5 are a and b. 'x' would be c.
[tex]12^2+5^2=c^2\\\\12^2=144\\5^2=25\\\\144+25=c^2\\\\169=c^2\\\\\sqrt{169}=\sqrt{c^2}\\\\\boxed{13=c}[/tex]
'x' should be equal to 13.
Write an expression to represent the product of 6 and the square of a number plus 15.
Answers
Answer:
6x^2 + 15
Step-by-step explanation:
We don't know what the square of a number is, so we represent it as x^2
The first part tells us to find the product of 6 and the square of a number, so
6x^2
The second part tells us to add 15 so,
6x^2 + 15
The expression that should be represented is [tex]6x^2 + 15[/tex]
Given that
The product of 6.The square of number + 15.Based on the above information,
Let us assume the number should be x
So, from the above information, the expression should be [tex]6x^2 + 15[/tex]
Therefore we can conclude that The expression that should be represented is [tex]6x^2 + 15[/tex]
Learn more about the equation here:brainly.com/question/21105092?
Someone help me plzz
Answers
Step-by-step explanation:
distance around the running track means to find the perimeter of whole solid figure
radius(r) = 30/2 =15m
perimeter = 50+ pi× r + 50+ pi × r
= 100 + 2 × pi ×r
= 100 + 2× 22÷7 × 15
= 1360/ 7 m
= 194.285 m
Two angles are adjacent and form an angle of 160. Their difference is 34. Find the angles
Answers
Answer:
The angles are 63 , 97
Step-by-step explanation:
Let one angle be x
As sum of two angles is 160, the other angle = 160 - x
Their difference = 34
x - [160- x] = 34
Use distributive property to remove the brackets
x - 160 + x = 34
Add like terms
x + x - 160 = 34
2x - 160 = 34
Add 160 to both sides
2x = 34 + 160
2x = 194
Divide both sides by 2
2x/2 = 194/2
x = 97°
One angle = 97°
Other angle = 160 - 97 = 63°
It says to find the area of the shaded square, but I not sure how to get the answer.
Answers
Answer:
68 square cm
Step-by-step explanation:
Interior square WXYZ is making four right triangles of equal bases (8 cm) and heights (2 cm) inside the square ABCD. Therefore,
Area of shaded Square = Area of square ABCD - 4 times area of one right triangle.
[tex] = {10}^{2} - 4 \times \frac{1}{2} \times 8 \times 2 \\ = 100 - 32 \\ = 68 \: {cm}^{2} [/tex]
Jeremy drove 180 miles in 3 hours. Find his average rate of change.
Answers
Answer:
60 miles per hour
Step-by-step explanation:
Total distance= 180 miles
Total time =3 hours
Average rate of change= ?
Distance= Rate × time
Make Time the subject of the formula
Time= Distance / Rate
Make average rate of change the subject of the formula
Average rate of change = Distance / time
= 180 miles / 3 hours
= 60 miles per hour
A chocolate company has a new candy bar in the shape of a prism whose base is a 1-inch equilateral triangle and whose sides are rectangles that measure 1 inch by 2 inches. These prisms will be packed in a box that has a regular hexagonal base with 2-inch edges, and rectangular sides that are 6 inches tall. How many candy bars fit in such a box
Answers
Regular hexagon with 2 inch edges contains 180*(6-2) = 180*4 = 720 degrees
That's 120 degrees in each of the corner pockets.
Drawing line segments from the center to each vertex creates 6 congruent isosceles triangles.
Selecting any one of these six triangles and dropping the height from the center to the edge
creates a 30-60-90 right triangle with height equal to the square root of 3 (rad3) and base measure 1.
So the area of each of these triangles is the square root of 3 , or in slang terms "rad 3", which means
the base area is 6*rad3.
The volume of the box is therefore 36*rad3
BASE AREA OF THE CANDY:
Dropping the height from one vertex to the opposite side of this equilateral triangle
creates 2 right triangles with base measure 1/2 and hypotneuse 1. So the height
must be rad3/2. The area of the entire equilateral triangle is rad3/4, which is the base area.
The volume of the candy is rad3/2
36*rad3 divided by rad3/2 =
36 rad3 times 2/rad3 <--- KFC : keep , change, flip
36 * 2 <-- rad3 cancels out
72 candies will fill the box.
Use slope-intercept form, y = mx + b, to find the value for the y-intercept (b) of a line that has a slope of 6 and passes through the point (3, –5)
Answers
Answer:
y=6x-23
Step-by-step explanation:
-5=6(3)+b
-5=18+b
b=-23
If this helps, plz give brainly, I rlly need it!
Answer:
6x-23
Step-by-step explanation:
find the value of X in X-X³=17
Answers
Answer:
Step-by-step explanation:
Step1: find the interval of roots. Consider -3 and -2
[tex]f(-3) = -7 <0[/tex]
[tex]f(-2) = 18 >0[/tex]
Hence, the root must be on [-3,-2]
Step2: consider the middle point -2.5
[tex]f(-2.5) = 3.875 >0[/tex]
Then, the root must be on [-3, -2.5]
Step 3: Repeat step 2 by finding the value of f at the middle point -2.75
[tex]f(-2.75) = -1.0468 <0[/tex]
Step 3: Repeat step 2 by finding the value of f at the middle point of the interval [-2.75,-2.5] which is -2.625
[tex]f(-2.625) = 1.537 >0[/tex]
Step4: Repeat step 2 on [-2.75, -2.625]
Repeat step 2 until you got the root which is -2.701
Please help! Brainliest answer gets 10 points! what is x^2+x^4?
Answers
Answer:
Step-by-step explanation:
You cannot add these because they are not like. IF you have a value for x, then the expression could be evaluated at the x value, but you can't add them.
PLEASE HELP f(x)=x^2 and g(x)=(x-3)^2+2 Describe how the graph of g(x) relates to the graph of its parent function, f(x). (HINT: Think about how f(x) was shifted to get g(x))
Answers
Answer:
The graph f(x) was shifted 3 units to the right and shifted 2 units up to get the graph of g(x).
Step-by-step explanation:
From the original graph to the transformed one, we can see that the transformations (x - 3) and + 2 were added to the equation.
The (x - 3) means that the x-value of the vertex will increase by 3, meaning that the graph will shift 3 units to the right.
The +2 will increase the y-value of the vertex by 2, meaning that the graph will move up 2 units.
So, the graph of g(x) relates to f(x) as it is a transformation 3 units to the right and 2 units upwards.
ILL GIVE BRAINLIEST!!!! HELP
Two planes have a cruising speed of 750 km/h without wind. The first plane flies for 13 hours against a constant headwind. The second plane flies for 11 hours in the opposite direction with the same wind (a tailwind). The second plane flies for 250 km less than the first plane. Determine two equations that could be used to solve for the wind speed,w, and the distance traveled by the first plane,d.
1. (750+w)(13)=d (750+w)(11)=d+250 2. (750−w)(13)=d (750+w)(11)=d−250 3. (750+w)(13)=d (750−w)(11)=d−250 4. (750−w)(13)=d (750−w)(11)=d+250
Answers
Answer:
The correct option is;
2. (750 - w)(13) = d (750 + w)(11) = d - 250
Step-by-step explanation:
The items with information given are;
The cruising speed of the planes = 750 km/h
The first plane flies against a constant headwind = w
The second plane flies against a constant tailwind in magnitude to the headwind
The time duration of flight of the first plane = 13 hours
The time duration of flight of the second plane = 11 hours
The distance flown by the second plane = The distance flown by the first plane - 250 km
When we take the headwind magnitude as, w and the distance flown by the first plane as d, we have;
Speed of flight of the first plane = 750 - w
Speed of flight of the second plane = 750 + w
Therefore, the distance flown by the first plane in 13 hours is given as follows;
(750 - w) × (13) = d
Then we have;
The distance flown by the second plane in 11 hours is (750 + w) × (11) = d.
The correct option is (750 - w)(13) = d, (750 + w)(11) = d - 250
-2(8 - 1)= complete the following statement
Answers
We simplify the expression by subtracting 1 from 8, resulting in 7. We then multiply 7 by -2 to obtain the final answer of -14.
To simplify the given expression, -2(8 - 1), we can start by evaluating the expression inside the parentheses,
8 - 1 = 7
Now, we substitute this value back into the original expression:
-2(7)
Multiplying -2 by 7, we get:
-2 * 7 = -14
Therefore, -2(8 - 1) simplifies to -14.
In this case, we simplified the expression inside the parentheses first and then applied the multiplication operation. It's important to remember that when there is a negative sign in front of parentheses, it distributes to each term inside the parentheses. So, -2 multiplied by 8 gives -16, and -2 multiplied by -1 gives +2. The sum of -16 and +2 is -14.
In summary, when we evaluate the expression -2(8 - 1), the result is -14. This means that if we follow the order of operations (parentheses first, then multiplication), we simplify the expression by subtracting 1 from 8, resulting in 7. We then multiply 7 by -2 to obtain the final answer of -14.
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complete the square to solve
f(x)=x^2-6x+5
Answers
Explanation:
x^2 - 6x + 5 = 0
(x^2 - 6x + 9) + 5 - 9 = 0
(x - 3)(x - 3) - 4 = 0
(x - 3)^2 = 4
x - 3 = +-2 (sqrt both sides)
x - 3 = 2
x = 5
x - 3 = -2
x = 1
convert the equation f(x)=1/2x^2+3x-2 to vertex form
Answers
Answer:
Step-by-step explanation:
Hello, please consider the following.
The "vertex form" is as below.
[tex]y=a(x-h)^2+k\\\\\text{Where (h, k) is the vertex of the parabola.}\\[/tex]
Let's do it!
[tex]f(x)=\dfrac{1}{2}x^2+3x-2\\\\f(x)=\dfrac{1}{2}\left(x^2+3*2*x\right) -2\\\\f(x)=\dfrac{1}{2}\left( (x+3)^2-3^2\right)-2\\\\f(x)=\dfrac{1}{2}(x+3)^2-\dfrac{9}{2}-\dfrac{4}{2}\\\\f(x)=\dfrac{1}{2}(x+3)^2-\dfrac{9+4}{2}\\\\\large \boxed{\sf \bf \ \ f(x)=\dfrac{1}{2}(x+3)^2-\dfrac{13}{2} \ \ }[/tex]
Thank you.
30 POINTS!! Quadratic function F(x) =2x^2- 4x- 6 is shown below. Which describes the domain of this function.
A. All real numbers greater than or equal to -8
B. All real number less than or equal to -8
C. All real number greater than 10
D. All real numbers
Answers
Answer:
D. All real numbers
Step-by-step explanation:
The domain is the set of values that can be used for x. There is no restriction on x, so the domain is all real numbers.
Answer:
all real numbers
Step-by-step explanation:
The domain is the possible input values
Since x can be any value, the domain is all real numbers
Please help. Calculate the area of the shaded region in each figure use 3.14 for π and round to the nearest 10th if necessary
Answers
Explanation:
Find the area of circle:
A = 3.14 x 5^2
A = 3.14 x 25
A = 78.5 cm^2
Find the area of rectangle:
A = 3 x 4
A = 12
Find area of shaded region:
A(shaded) = A(circle) - A(rectangle)
A = 78.5 - 12 = 66.5 cm^2
ACME Hardware is introducing a new product called Greener Cleaner. Complete the table by finding the cost per milliliter for each size based on the sales price. One liter is 1,000 milliliters. (Answer the questions too, please!)
Answers
Answer:
Step-by-step explanation:
a). 'Per ml' cost of the small size = [tex]\frac{\text{Sale price of small cane}}{\text{Amount of liquid}}[/tex]
= [tex]\frac{4.50}{250}[/tex]
= $0.018
'Per ml' cost of the medium size = [tex]\frac{\text{Sale price of medium cane}}{\text{Amount of liquid}}[/tex]
= [tex]\frac{9.95}{500}[/tex]
= $0.0199
'Per ml' cost of the large size = [tex]\frac{\text{Sale price of large cane}}{\text{Amount of liquid}}[/tex]
= [tex]\frac{16.95}{1000}[/tex]
= $0.01695
Therefore, expression to compare per ml cost of three containers will be,
$0.0199 > $0.018 > $0.01695
b). Least expensive way to buy the cleaner is to choose the container with least per ml cost.
Cost of 1500 ml cleaner = Cost of 1000 ml cleaner + Cost of 500 ml of cleaner
= Cost of 1000 ml cleaner container + Cost of 'n' containers of 250 ml container
Total cost of 1500 ml = $16.95 + $4.50n
= 16.95 + 2(4.5) [For n = 2]
= $25.95
c). Most expensive way to purchase 1500 ml cleaner is to choose the most expensive cleaners
Cost of 1500 ml cleaner = Cost of 'n' containers of medium size containers
= 9.95(n)
= 9.95(3)
= $29.85
5 3/4 - (-3 7/8) = H
What is H ?
Answers
Answer:
Step-by-step explanation:
convert mixed fraction into improper fraction
[tex]5\frac{3}{4}=\frac{23}{4}\\\\\\3\frac{7}{8}=\frac{31}{8}\\\\5\frac{3}{4}-[-3\frac{7}{8}]=\frac{23}{4}+\frac{31}{8}\\\\=\frac{23*2}{4*2}+\frac{31}{8}\\\\=\frac{46}{8}+\frac{31}{8}\\\\=\frac{46+31}{8}\\\\\\=\frac{77}{8}\\\\=9\frac{5}{8}[/tex]
Answer:
9 5/8.
Step-by-step explanation:
5 3/4 - (-3 7/8)
= 5 3/4 + 3 7/8
= 5 + 3 + 3/4 + 7/8
= 8 + 3/4 + 7/8
The LCD of 4 and 8 is 8 so we get
8 + 6/8 + 7/8
= 8 + 13/8
= 8 + 1 5/8
= 9 5/8.
Can someone plz help me ASAP!!!!!!!!
Answers
Answer:
A) The number halfway between -2 and 6 is 2.
B) -10 is halfway between -18 and 8
The functions q and r are defined as follows
g(x) = -2x-2
r(x) = x² – 2
Find the value of r(q(4)).
r(9 (4)) =
Answers
Answer:
98
Step-by-step explanation:
So we have the two functions:
[tex]g(x)=-2x-2\text{ and } r(x)=x^2-2[/tex]
And we want to find the value of r(g(4)).
To do so, first find the value of g(4):
[tex]g(x)=-2x-2\\g(4)=-2(4)-2\\[/tex]
Multiply:
[tex]g(4)=(-8)-2[/tex]
Subtract:
[tex]g(4)=-10[/tex]
Now, substitute this into r(g(4)):
[tex]r(g(4))\\=r(-10)[/tex]
And substitute this value into r(x):
[tex]r(-10)=(-10)^2-2[/tex]
Square:
[tex]r(-10)=100-2[/tex]
Subtract:
[tex]r(-10)=98[/tex]
Therefore:
[tex]r(-10)=r(g(4))=98[/tex]
Answer:
Step-by-step explanation:
A driver of a car stopped at a gas station to fill up his gas tank. He looked at his watch, and the time read exactly 3:40 p.m. At this time, he started pumping gas into the tank. At exactly 3:44, the tank was full and he noticed that he had pumped 6 gallons.
Answers
Answer:
3.625 gpm
Step-by-step explanation:
Help!!!! Which number line shows the solution to 6 + (−6)?
Answers
Answer: Hi!
The solution to positive 6 and -6 is 0. A negative and a positive of the same absolute value cancel out.
Hope this helps!
Answer:
the answer is zero !
Step-by-step explanation:
when a negative and a positive of the same number go against each other they cancel out
X-5y=-15x−5y=−15x, minus, 5, y, equals, minus, 15 Complete the missing value in the solution to the equation. (-5,(−5,left parenthesis, minus, 5, comma ))
Answers
Answer:
The missing value is 2. The coordinate will be (-5, 2)Step-by-step explanation:
The question is not properly written. Find the correct question below.
If x – 5y = -15 . Complete the missing value in the solution to the equation (-5, ____)
Let the coordinate of the variables be (x, y). Comparing the coordinates (x, y) with the given coordinate (-5, __), we will discover that x = -5. To get the y coordinate, we will substitute x = -5 into the given expression as shown;
If x – 5y = -15
-5 - 5y = -15
Adding 5 both sides
-5-5y+5 = -15+5
-5y = -10
Dividing both sides by -5;
-5y/-5 = -10/-5
y = 2
Hence the missing value in the solution of the equation is 2. The coordinate will be (-5, 2)
Answer:
2
Step-by-step explanation:
I did the khan :)
An octagonal pyramid ... how many faces are there, how many vertices and how many edges? A triangular prism ... how many faces are there, how many vertices and how many edges? a triangular pyramid ... how many faces are there, how many vertices and how many edges?
Answers
1: 8 faces and 9 with the base 9 vertices and 16 edges
2: 3 faces and 5 with the bases 6 vertices and 9 edges
3: 3 faces and 4 with the base 4 vertices and 6 edges
1: 8 faces and 9 with the base 9 vertices and 16 edges
2: 3 faces and 5 with the bases 6 vertices and 9 edges
3: 3 faces and 4 with the base 4 vertices and 6 edges
Marcus is shopping for pants. The available styles are boot cut (B), skinny (S), and relaxed fit (R). Make an organized list to show all possible outcomes if he buys two new pairs of pants.
Answers
Answer:
list in the explanation
Step-by-step explanation:
BOOT x2
SKINNY x2
RELAXED x2
BOOT, SKINNY
BOOT, RELAXED
SKINNY, BOOT
SKINNY, RELAXED
RELAXED, BOOT
RELAXED, SKINNY
The solution set is given by Set A = { BB , SS , RR , BS , BR , SR } , where B , S and R are boot cut (B), skinny (S), and relaxed fit (R) respectively
What is union and intersection of sets?The union of two sets A and B is the set of all those elements which are either in A or in B, i.e. A ∪ B, whereas the intersection of two sets A and B is the set of all elements which are common. The intersection of these two sets is denoted by A ∩ B
The union of two sets is a new set that contains all of the elements that are in at least one of the two sets
The intersection of two sets is a new set that contains all of the elements that are in both sets
Given data ,
Let the set be represented as A
Now , the equation will be
Marcus is shopping for pants and the available pants are boot cut (B), skinny (S), and relaxed fit (R)
He wants to buy 2 pair of pants , and the possible ways of 2 pants are
Set A = { BB , SS , RR , BS , BR , SR }
So , the total number of elements in set A = 6 pairs
Therefore , the value of A is 6 pairs
Hence , the set A is { BB , SS , RR , BS , BR , SR }
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What ratio of 25 dextrose and 10% dextrose should be mixed to make a 20% Dextrose? Comments for What Ratio of 25% Dextrose and 10% Dextrose to make 20% Dextrose? 10 parts 25% and 5 parts 10% solution equals 20% mixture.
Answers
Answer:
10:5 OR 2:1
Step-by-step explanation:
Let x be the parts of 25% dextrose and
y be the parts of 10% dextrose are mixed so that
20% dextrose mixture is obtained.
amount of dextrose in the mixture will be 20% of (x+y).
We have to find the value of [tex]\frac{x}y \ OR\ x:y[/tex]
Now, we can apply the concept that sum of amount of dextrose in the two liquids will be equal to the amount of dextrose in the mixture.
[tex]\Rightarrow x \times 25\% + y \times 10\%=(x+y)\times 20\%\\\Rightarrow x \times\dfrac{25}{100} + y \times \dfrac{10}{100}=(x+y)\times \dfrac{20}{100}\\\Rightarrow x \times25 + y \times 10=(x+y)\times 20\\\Rightarrow 25x + 10y=20x+20y\\\Rightarrow 25x -20x =20y-10y\\\Rightarrow 5x=10y\\\Rightarrow \dfrac{x}{y} = \dfrac{10}{5}\\\Rightarrow \bold{x:y=10:5\ OR\ 2:1}[/tex]
So, the answer is 10:5 or 2:1.
Answer:
4.90% is approximately the new Dextrose concentration.
Explanation:
Volume by Volume percent is given by ;
Volume percentage of dextrose solution = 5%
In 100 mL of solution 5 ml of dextrose is present.
Now, volume sterile water added was equal to the 40% of volume of dextrose volume.
So, volume of the sterile water added =
Total volume of the solution after addition of water = 100 mL + 1 mL = 102 mL
New concentration of dextrose will be;
4.90% is approximately the new Dextrose concentration.
Step-by-step explanation:
A.) pinky bought 1 1/2 kg of apples and 5 1/4 kg of mangoes and 1 1/2 Kg of oranges. Find the total weight of fruits B.) If her family eats 3/4 Kg of apples and 2 1/2 kg of mangoes and 1/2 Kg of oranges. Find the weight of the fruits left (Can any one say the answer please with explanation if who say the answer first I will mark them as the brainliest)
Answers
Answer:
a) The total weight of fruits is [tex]8\,\frac{1}{4}[/tex] kilograms, b) The weight of the fruits left is [tex]4\,\frac{1}{2}[/tex] kilograms.
Step-by-step explanation:
a) The total weight of fruits ([tex]m_{T}[/tex]) is calculated by the following formula:
[tex]m_{T} = m_{a} + m_{m}+m_{o}[/tex]
Where:
[tex]m_{a}[/tex] - Total weight of apples, measured in kilograms.
[tex]m_{m}[/tex] - Total weight of mangoes, measured in kilograms.
[tex]m_{o}[/tex] - Total weight of oranges, measured in kilograms.
If [tex]m_{a} = 1\,\frac{1}{2} \,kg[/tex], [tex]m_{m} = 5\,\frac{1}{4}\,kg[/tex] and [tex]m_{o} = 1\,\frac{1}{2}\,kg[/tex], then:
[tex]m_{T} = 1\,\frac{1}{2}\,kg + 5\,\frac{1}{4}\,kg + 1\,\frac{1}{2}\,kg[/tex]
[tex]m_{T} = \frac{6}{4}\,kg + \frac{21}{4}\,kg + \frac{6}{4}\,kg[/tex]
[tex]m_{T} = \frac{33}{4}\,kg[/tex]
[tex]m_{T} = 8\,\frac{1}{4}\,kg[/tex]
The total weight of fruits is [tex]8\,\frac{1}{4}[/tex] kilograms.
b) The weight eaten by her family is determined by the following expression:
[tex]m_{E} = m_{a,e} + m_{m,e} + m_{o,e}[/tex]
Where:
[tex]m_{a,e}[/tex] - Eaten weight of apples, measured in kilograms.
[tex]m_{m,e}[/tex] - Eaten weight of mangoes, measured in kilograms.
[tex]m_{o,e}[/tex] - Eaten weight of oranges, measured in kilograms.
Given that [tex]m_{a,e} = \frac{3}{4}\,kg[/tex], [tex]m_{m,e} = 2\,\frac{1}{2}\,kg[/tex] and [tex]m_{o,e} = \frac{1}{2}\,kg[/tex], the weight eaten by her family is:
[tex]m_{E} = \frac{3}{4}\,kg + 2\,\frac{1}{2}\,kg + \frac{1}{2}\,kg[/tex]
[tex]m_{E} = \frac{3}{4}\,kg + \frac{10}{4}\,kg + \frac{2}{4}\,kg[/tex]
[tex]m_{E} = \frac{15}{4}\,kg[/tex]
[tex]m_{E} = 3\,\frac{3}{4}\,kg[/tex]
The weight of the fruits left is found by subtraction:
[tex]m_{R} = m_{T}-m_{E}[/tex]
[tex]m_{R} = 8\,\frac{1}{4} \,kg -3\,\frac{3}{4}\,kg[/tex]
[tex]m_{R} = \frac{33}{4}\,kg-\frac{15}{4}\,kg[/tex]
[tex]m_{R} = \frac{18}{4}\,kg[/tex]
[tex]m_{R} = 4 \,\frac{1}{2}\,kg[/tex]
The weight of the fruits left is [tex]4\,\frac{1}{2}[/tex] kilograms.
Use sigma notation to represent the sum of the first seven terms of the following sequence -4,-6,-8.....
Answers
Answer:Answer:
[tex]\sum\left {{7} \atop {1}} \right -n(3+n)[/tex]
Step-by-step explanation:
Given the sequence -4,-6,-8..., in order to get sigma notation to represent the sum of the first seven terms of the sequence, we need to first calculate the sum of the first seven terms of the sequence as shown;
The sum of an arithmetic series is expressed as [tex]S_n = \frac{n}{2}[2a+(n-1)d][/tex]
n is the number of terms
a is the first term of the sequence
d is the common difference
Given parameters
n = 7, a = -4 and d = -6-(-4) = -8-(-6) = -2
Required
Sum of the first seven terms of the sequence
[tex]S_7 = \frac{7}{2}[2(-4)+(7-1)(-2)]\\\\S_7 = \frac{7}{2}[-8+(6)(-2)]\\\\S_7 = \frac{7}{2}[-8-12]\\\\\\S_7 = \frac{7}{2} * -20\\\\S_7 = -70[/tex]
The sum of the nth term of the sequence will be;
[tex]S_n = \frac{n}{2}[2(-4)+(n-1)(-2)]\\\\S_n = \frac{n}{2}[-8+(-2n+2)]\\\\S_n = \frac{n}{2}[-6-2n]\\\\S_n = \frac{-6n}{2} - \frac{2n^2}{2}\\S_n = -3n-n^2\\\\S_n = -n(3+n)[/tex]
The sigma notation will be expressed as [tex]\sum\left {{7} \atop {1}} \right -n(3+n)[/tex]. The limit ranges from 1 to 7 since we are to find the sum of the first seven terms of the series.
Given that p=x^2-y^2/x^2+xy
I. Express p in the simplest form
ii. Find the value of p if x=-4 and y=-6
Answers
Answer:
p = - [tex]\frac{1}{2}[/tex]
Step-by-step explanation:
Given
p = [tex]\frac{x^2-y^2}{x^2+xy}[/tex] ( factorise numerator and denominator )
x² - y² ← is a difference of squares and factors as (x - y)(x + y)
x² + xy ← factor out x from each term
= x(x + y) , thus
p = [tex]\frac{(x-y)(x+y)}{x(x+y)}[/tex] ← cancel (x + y) on numerator/ denominator
= [tex]\frac{x-y}{x}[/tex] ← substitute x = - 4, y = - 6
= [tex]\frac{-4-(-6)}{-4}[/tex]
= [tex]\frac{-4+6}{-4}[/tex]
= [tex]\frac{2}{-4}[/tex] = - [tex]\frac{1}{2}[/tex]
