Answer:
Substitute each of the values into the expression.
1. 7(7)-3(4)+8-4
49-12+8-4
41
2. 6(5)-10/5
30-2
28
3. 3(1)^2+2^3
3(1)+8
11
4. 5(3)^2
5(9)
45
:)
Write the equation of the following parabolae in their canonical form and hence find their vertices, foci and directrix.
1.
[tex] {y}^{2} - 6y - 2x + 19 = 0[/tex]
2.
[tex] {x}^{2} + 4x + 4y + 16 = 0[/tex]
Given:
y² - 6y - 2x + 19 = 0This is a horizontal parabola.
Canonical form of horizontal parabola is:
4a(x - h) = (y - k)², where (h, k) is vertexFocus is:
F(h + a, k)Directrix is:
x = h - aConvert the equation:
y² - 6y - 2x + 19 = 0y² - 6y + 9 - 2x + 10 = 0(y - 3)² = 2x - 10(y - 3)² = 4(1/2)(x - 5)We got:
h = 5, k = 3, a = 1/2Focus is:
F(5 + 1/2, 3) = F(5.5, 3)Directrix is:
x = 5 - 1/2 = 4.5#2Given:
x² +4x + 4y + 16 = 0This is a vertical parabola.
Canonical form of vertical parabola is:
4a(y - k) = (x - h)², where (h, k) is vertexFocus is:
(h, k + a)Directrix is:
y = k - aConvert the equation:
x² + 4x + 4y + 16 = 0x² +4x + 4 + 4y + 12 = 0(x + 2)² = -4y - 12(x + 2)² = 4(-1) (y + 3)We got:
h = - 2, k = -3, a = - 1Focus is:
F(-2, -3 - 1) = F(-2, - 4)Directrix is:
y = -3 - (-1) = - 2What number is furthest from 0 on a number line? 16 or 18?
can anyone please help me asap? thanks in advance.
1. In three minutes Alex typed 120 words. At this rate, how long would it take him to type a 4800 word assignment?
2. The ratio of the length to the width of the Canadian flag is 2:1. What is the width of a 50 cm long Canadian flag?
3. A bulk nut mixture is priced at $1.14 per 100 grams. How much is 600g of this mixture?
please show ur work for each.
Answer:
1. 2 hours
2. 25cm
3. 6.84
Step-by-step explanation:
120÷3=40
4800÷40=120 so 2 hours
for the second one just divide 50 in half
for 3 just do $1.14×6
Answer:
1. 120 min
2. 25 cm
3. $6.84
Step-by-step explanation:
1. 120 words : 3min
multiply each side by 40 because 120 words times 4 is 4800 words
4800 words : 120min
2. 2 : 1 = length : width
multiply each side by 25 because 2 times 25 is 50 cm
50 cm : 25 cm
3. $1.14 : 100 grams
multiply each side by 6 because 100 grams times 6 is 600 grams
$6.84 : 600 grams
The 1st one was doable, but I don't understand the 2nd Question.
Answer: ? What are you talking about?
Step-by-step explanation:
If an atom has 5 protons, 7 neutrons and 5 electrons what is the mass number of the atom?
Please help quick!
No links!
Answer:
7+5=12
Step-by-step explanation:
To calculate the mass number of an atom, you have to add the protons and the neutrons. We have 7 neutrons and 5 protons, so your mass number would be 12. Let me know if you have any further questions. :)
Class 10R sat a test.
The mean mark for the class was 70%.
There are 30 students in class 10R, 20 of whom are boys.
The mean mark for the boys in the test was 62%.
Work out the mean mark for the girls.
86%
Step-by-step explanation:30 students in the class with a mean average of 70% can be expressed as:
total class percent / 30 = 70%
Rearranged, this gives that the class achieved a total of 30x70 or 2100%.
20 boys in the class with a mean average of 62% can be expressed as:
total boys percent / 20 = 62%
Rearranged, this gives that the boys achieved a total of 20x62 or 1240%.
This means that the girls achieved 2100 - 1240 so 860%.
Because there are 30 students and 20 boys, there are 10 girls.
Then work out the mean with a total of 860% and 10 girls.
860/10 = 86%.
the perimeter of rectangle is 2x² + 4x - 4y. its length is (2x - 3y). find the breadth of rectangle
plz help fast plz plz
Perimeter = 2 (l + b)
2x² + 4x - 4y = 2 {(2x - 3y) + b}
2x² + 4x - 4y = (4x - 6y) + 2b
2x² + 4x - 4y - (4x - 6y) = 2b
2x² + 4x - 4y - 4x + 6y = 2b
2x² + 2y = 2b
(2x² + 2y)/2 = b
x² + y = b
Breadth = x² + y
Find the surface area of the square pyramid below.
Answer:
Step-by-step explanation:
Answer:
96 cm or B
Step-by-step explanation:
Base-l*w, 6*6, 36
Side 1-(h*w)1/2, (30)1/2, 15
Side 2-Same as 1
Side 3-Same as 1
Side 4-Same as 1
15+15=30, 15+15=30, 30+30=60, 60+36=96
96 cm
solve pls brainliest
1) No, because it is a repeating decimal
2) Yes, because it is neither terminating nor repeating
3) Yes, because it is a terminating decimal
4) No, because it is a repeating decimal
why are prefixes used in naming covalent compounds
A. oxidation states of the atoms are identified with prefixes
B. the atoms can have different numbers of valence electrons
C. the prefixes identify the only way the atom can combine
D. the same atoms can combine in more than one ratio
Answer:
the atoms can have different numbers of valence electrons
Simplify.
x2+2x−3/
x−4/
2x2+5x−3/
x^2−16
x2−x−12/2x−3
x2−5x−4/2x−1
x2+3x−4/2x−1
x2+x−12/2x−3
Answer:
x^2 + 7x- 3/x - 3/x^2 -16
Step-by-step explanation:
Key: ( ^ ) means exponent
= x^2 + 2x- 3/x -2x^2 + 5x- 3/x^2 -16
= x^2 - 2x^2 + 2x+5x - 3/x- 3/x^2 -16
= x^2 - 2x^2 = -x^2
= -x^2 + 2x + 5x- 3/x- 3/x^2-16
As you see you add 2x and the 5x and got 7x
= Answer : x^2 + 7x- 3/x - 3/x^2 -16
Answer:
I think the answer is x^2+3x-4/2x-1
Your above-ground pool has sprung a leak, and you do not have a way to fix it. At 12 noon, the water in the pool is 5 feet deep (in other words, the water level is 5 feet above the ground). You are not sure how quickly the pool level is falling, so you check again after 40 minutes and see that the height of the water level is now feet. You notice that there is a relationship between the time that has passed to the height of the water level in the pool.
Answer:
Step-by-step explanation:
hi please help me with part b and can you see if i did a correctly pls?
a is right its 58
and in my opinion i think b would be 58*5=290 cents, since nickel is worth 5 cents.
but gotta check other people's answers
line j passes through the point (-4,10) and (2,-8). Line k passes through the point (1,2) and is parallel to line j. Find an equation for line k.
Answer:
344444444433333338694
Step-by-step explanation:
Answer: y = -3x+5
Step-by-step explanation:
if 5/6 of the 30 motorcycles were new, how many motorcycles were used
Answer:
5 Motorcycles are used
30÷6= 5
5×5= 25
30-24=5
so the answer is 5
Answer:
5 out of the 30 motorcycles are used
Step-by-step explanation:
First, we should look at what we know. We know that there are 30 motorcycles in total. As a fraction, that'd be 30/30. We also know that of that 30, the equivalent of 5/6 are brand new.
Our next step is to figure out how much 5/6 is out of 30. Since we know that in total there 30/30 motorcycles, we need to convert 5/6 to have a denominator of 30. So what times 6 equals 30.
30 ÷ 6 = ? opposite of 6 x ? = 30
5 divide
So now we now that 6 times 5 equals 30. What we do to the denominator we must do to the numerator.
[tex]\frac{5}{6}[/tex] × [tex]\frac{5}{5}[/tex]
[tex]\frac{25}{30}[/tex]
Now we know that 25 of the 30 motorcycles are new and all we need to do is subtract that 25 from the total 30 to get 5. This tells us that 5 of the total motorcycles are used.
I hope this helped :)
Express in vertex form
Y=2x^2 - 2x - 5
Answer:
y = 2(x - [tex]\frac{1}{2}[/tex] )² - [tex]\frac{11}{2}[/tex]
Step-by-step explanation:
y = 2x² - 2x - 5 ← factor out 2 from the first 2 terms
= 2(x² - x) - 5
Using the method of completing the square
add/subtract (half the coefficient of the x- term)² to x² - x
y = 2(x² + 2(- [tex]\frac{1}{2}[/tex] ) x + [tex]\frac{1}{4}[/tex] - [tex]\frac{1}{4}[/tex] ) - 5
= 2(x - [tex]\frac{1}{2}[/tex] )² + 2(- [tex]\frac{1}{4}[/tex] ) - 5
= 2(x - [tex]\frac{1}{2}[/tex] )² - [tex]\frac{1}{2}[/tex] - 5
= 2(x - [tex]\frac{1}{2}[/tex] )² - [tex]\frac{11}{2}[/tex] ← in vertex form
What are the roots of the equation 4x^2+24x+45=0 in simplest a+bi form?
Answer:
X=(-1.5, 7.5)
Step-by-step explanation:
Simplifying
4x2 + -24x + -45 = 0
Reorder the terms:
-45 + -24x + 4x2 = 0
Solving
-45 + -24x + 4x2 = 0
Solving for variable 'x'.
Factor a trinomial.
(-3 + -2x)(15 + -2x) = 0
Set the factor '(-3 + -2x)' equal to zero and attempt to solve:
Simplifying
-3 + -2x = 0
Solving
-3 + -2x = 0
Move all terms containing x to the left, all other terms to the right.
Add '3' to each side of the equation.
-3 + 3 + -2x = 0 + 3
Combine like terms: -3 + 3 = 0
0 + -2x = 0 + 3
-2x = 0 + 3
Combine like terms: 0 + 3 = 3
-2x = 3
Divide each side by '-2'.
x = -1.5
Simplifying
x = -1.5
Set the factor '(15 + -2x)' equal to zero and attempt to solve:
Simplifying
15 + -2x = 0
Solving
15 + -2x = 0
Move all terms containing x to the left, all other terms to the right.
Add '-15' to each side of the equation.
15 + -15 + -2x = 0 + -15
Combine like terms: 15 + -15 = 0
0 + -2x = 0 + -15
-2x = 0 + -15
Combine like terms: 0 + -15 = -15
-2x = -15
Divide each side by '-2'.
x = 7.5
Simplifying
x = 7.5
Solution
x = {-1.5, 7.5}
Find the number that makes the ratio equivalent to 6:3 :9
A store owner has 65.5 pounds of candy. If he splits the candy equally into 5 boxes, how many pounds of candy will each box contain?
Answer: Each box of candy would contain 13.1 pounds of candy.
Step-by-step explanation:
Divide 65.5 by 5. Hope this helps!
can someone help me 5/4/7 + 1/3/4
Please check the attached image for the steps.
Answer = 11/42 = 0.261
____
RainbowSalt2222 ☔
Which number is a rational number? OA √15 OB. 2.6457513110... O c. 17.156 OD. 3√85
Answer:
"O c. 17.156"
Step-by-step explanation:
A is not a rational number because it cannot be written as a fraction [with two integers] or an integer (the square root of 15 is equal too 3.87298334...)
B is not a rational number because it also goes on forever, just like A.
C is a rational number because it does not go on forever.
D is like A and B, it goes on forever.
Have a nice day!
I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)
- Heather
Represent the following expressions as a power of the number a (a≠0): (a^2*a^2*a^2)^3
express the followinf percentage as a fraction
a) 6 3/5%
Answer:
6.6/100 or 3.3/5
Step-by-step explanation:
6.6% or 6 3/5% now since those are all out of 100 (since percentages) you just put #/100 and get your fraction
What is the next term in the sequence 58, 47, 36, 25,. ? –58 –8 14 69.
Answer:
14
Step-by-step explanation:
58, 47, 36, 25,. ?
Each term is 11 less than the preceding term
the term after 25 will be
25 - 11 = 14
Sully built a shelf 8 5/8 inches wide for his DVD collection. If each DVD is 3/8 inches
wide, how many can he fit on the new shelf?
Answer:
23
Step-by-step explanation:
8 5/8 = 69/8
Each DVD is 3/8 inches
Ignore the denominators
We have 69 and 3
69 is 23 times bigger than 3, so 23 DVD's can fit
Mary has 2 1/5 hours before she needs to meet her friend. She needs to take care of 7 chores before then. How much time can she allocate to each chore?
around 19 minutes ^^
(18.85 minutes)
Mary can allocate to each chore around 18.85 minutes.
What is the unitary method?The unitary method is a method for solving a problem by the first value of a single unit and then finding the value by multiplying the single value.
It is given that Mary has 2 1/5 hours before she needs to meet her friend. She needs to take care of 7 chores before then.
Hence, we get
2 and 1/5 hours = 132 minutes (120 + 12)
thus, Mary will have 132/7 = 18.85714285714286 minutes for each chore.
Or around 18.85 minutes for each chore
Therefore, she can allocate to each chore around 18.85 minutes.
Learn more about the unitary method;
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Please help me with this homework
WILL GIVE BRAINLIEST
PLEASE HELP
(LINKS/WRONG ANSWERS/WANNA BE FUNNY ANSWERS/NO ANSWERS/. WILL BE REPORTED!!!
Which function has the graph shown below? *
a. f(x) = x² - 4
b. f(x) = x² + 4
c. f(x) = (x + 4)²
d. f(x) = (x - 4)² opps dont forget to change the sign
Answer:
C
Step-by-step explanation:
yeah-ya......... right?
combine like terms and solve x
12x + 3 - 4x - 6 = 5
5x - 4 + 7 + 6x - 4x = 24
Answer:
12x + 3 - 4x - 6 = 5
x=1
5x - 4 + 7 + 6x - 4x = 24
x=3
