In any artihmetic sequence, consecutive terms differ by a fixed constant c. So given the first term a, the second term is a + c, the third terms is a + 2c, and so on, up to the n-th term a + (n - 1)c.
If the 15th term is 40, then
40 = -12 + (15 - 1) c ==> c = 52/14 = 26/7
We can then write the n-th term as
-12 + (n - 1) 26/7 = (26n - 110)/7
The sum of the first 15 terms is then
[tex]\displaystyle \sum_{n=1}^{15}\frac{26n-110}7 = \frac{26}7\sum_{n=1}^{15}n - \frac{110}7\sum_{n=1}^{15}n = \boxed{210}[/tex]
Another way to compute the sum: let S denote the sum,
S = -12 - 58/7 - 32/7 + … + 228/7 + 254/7 + 40
Reverse the order of terms:
S* = 40 + 254/7 + 228/7 + … - 32/7 - 58/7 - 12
Notice that adding up terms in the same position gives the same result,
-12 + 40 = 28
-58/7 + 254/7 = 28
-32/7 + 228/7 = 28
so that
S + S* = 2S = 28 + 28 + 28 + … + 28 + 28 + 28
There are 15 terms in the sum, so
2S = 15×28 ==> S = 15×28/2 = 210
y is the element of the set {1.5, 7.2, 3.4, 4.1, 8.9, .75} and 5Y ÷ 6 is an integer. What is the value of Y
Answer:
7.2
Step-by-step explanation:
5y = 5 *7.2 = 36
36 ÷ 6 = 6
So, y = 7.2
Problem 7:
show that 4^n + 4^n+1 + 4^n+2 + 4^n+3 + 4^n+4 is divisible by 11 for any positive integer
4ⁿ + 4ⁿ⁺¹ + 4ⁿ⁺² + 4ⁿ⁺³ + 4ⁿ⁺⁴
= 4ⁿ (4⁰ + 4¹ + 4² + 4³ + 4⁴)
= 4ⁿ × 341
= 4ⁿ × 11 × 31
reduce
0.1 x squared - 8.1 x + 8 = 0 to
2x squared - x + 80 = 0
Answer:
x = 8
x = -10
Step-by-step explanation:
Please help out with this question..
Answer:
Step-by-step explanation:
C = 16 * 3 = 48
Need help ASAp plz and thank you
Answer:
pls use calculater
Step-by-step explanation:
because i also dont know now what shall i do so its a good suggestion for you i hope
A basketball team received a care package and split it evenly among
5 players. If each player received 9 candy bars, how many candy bars
were in the care package?
Help please
Answer:
45
Step-by-step explanation:
9x5
Given: F(x) = 2x^2+ 1, G(x) = 2x - 1, H(x) = x
F-2) =
Answer:
Step-by-step explanation:
Find the missing side or angle.
Round to the nearest tenth.
b=3
a=9
c=11
C= ?
Answer:
C=125°
Step-by-step explanation:
Hi there!
To find angle C, we can use the cosine law:
[tex]cosC=\frac{a^2+b^2-c^2}{2ab}[/tex]
Plug in the given information
[tex]cosC=\frac{9^2+3^2-11^2}{2(9)(3)}[/tex]
[tex]cosC=\frac{-31}{54}[/tex]
[tex]C=cos^-^1(\frac{-31}{54})[/tex]
[tex]C=cos^-^1(\frac{-31}{54})\\C=125[/tex]
Therefore, angle C is approximately 125 degrees.
I hope this helps!
order the set of irrational numbers from least to greatest
Answer:
answer is A
hope it helps please mark as brainliest answer and give me thanks
#Dhruv hereA regular hexagon has a radius of 20 in. What is the approximate area of the hexagon?
600 in.2
1,038 in.2
1,200 in.2
2,076 in.2
Answer:
B
Step-by-step explanation:
A=(3*sqrt(3)*a^2)/2
A=(3*sqrt(3)*400)/2=1038
Answer:
B. 1,038 in.2
Step-by-step explanation:
please answer the question below! first to answer correctly, I will mark as brainliest.
The probability of not winning would be :
1 - probability of winning
This is written as:
1 - n/n+3
Now to simplify as a single fraction rewrite as:
N+3/n+3 - n/n+3
Simplify to get : 3/n+3
If the discriminant of an equation is zero, which of the following is true of the equation?
[tex]\sf Your \: question \: is \: incomplete. \: [/tex]
______________________
[tex]\sf \: I \: believe \: this \: is \: the \: answer \: you \: wanted[/tex] ⟹
[tex]\sf If \: the \: discriminant \: of \: an \: equation \: is \: zero, \: then \\ \sf \: the \: equation \: will \: have \:\underline{ 1 \: real \: solution \: with \: real \: and \: equal \: roots}.[/tex]
[tex]\boxed{ \sf{Explanation}} [/tex]
[tex]\sf If \: discriminant \: of \: quadratic \: equation \: ax^{2} + bx + c \: \\ \sf is \: b^{2} - 4ac = 0 \: then \: it \: will \: have \\ \sf↦\underline{1 \: real \: solution \: with \: real \: and \: equal \: roots.} [/tex]
Answer:
see explanation
Step-by-step explanation:
If b² - 4ac = 0
Then the roots are real and equal
plsssss helpp in the next 2 min gives 10 points
Answer:
The answer is 144,5
Step-by-step explanation:
144,5/170×100 =85%
please help me out really need help
Answer:
B
add the two together.... 5x^3 is the only cube A or B only x is 6x and only B has that
Step-by-step explanation:
Answer:
your answer is B
[tex]f(x)=2x^{2} +6x-4[/tex]
[tex]g(x)=5x^{3} -6x^{2} -3[/tex]
[tex](f+g)x=2x^{2} +6x-4+5x^{3} -6x^{2} -3[/tex]
[tex]=5x^{3} -4x^{2} +6x-7[/tex]
OAmalOHopeO
evaluate and solve: y + 3 = –y + 9
The value of y is 3.
Answer:
Solution given;
: y + 3 = –y + 9
add +y on both term
y+y+3=-y+y+9
subtract both side by 3
2y+3-3=9-3
2y=6
divide both side by 2
2y/2=6/2
y=3
Answer:
y = 3
Step-by-step explanation:
y + 3 = –y + 9
Add y to each side
y+y + 3 = –y +y+ 9
2y +3 = 9
Subtract 3 from each side
2y+3-3 = 9-3
2y = 6
Divide by 2
2y/2 = 6/2
y = 3
If m ≠ 1 and mn - 3 = 3 - n , then what is the value of n?
A) 6/ m+1
B) 6/ m-1
C) 6/ m+n
D) 6/ m-n
[tex]n = \frac{6}{m + 1} [/tex]
Hope it helps you...
The value of n is n= 6/( m+1).
What is expression?An expression is a set of terms combined using the operations +, – , x or , /.
Given:
mn - 3 = 3 - n
mn + n = 6
n(m+ 1) =6
n= 6/( m+1)
Learn more about expression here:
https://brainly.com/question/14083225
#SPJ2
Someone please help out
Answer:
Option D
Step-by-step explanation:
Alternate Interior angles are angles that are on the opposite sides of the transversal line (which is the line that cuts across the two parallel lines) and are on the inside of the two parallel lines which in this case is Option D.
How many solutions does it have? Pls help
Answer:
2 solutions
i hope this will help you
Solve the following system of equations by graphing. Label the solution and all intercepts.
4x-2y=8
y=1/2x+2
Please show me also how to graph it. Thanks a ton!
Answer:
(4,4)
y = 4
x = 4
Step-by-step explanation:
First we need to input y = 1/2x + 2 into 4x - 2y = 8.
4x - 2 (1/2x + 2) = 8 <-- Then solve
4x - 1x + -4 = 8
3x - 4 = 8
+4 +4
---------------------
3x = 12
3 3
x = 4
Now we need to use x and apply it to find y.
y = 1/2x + 2
y = 1/2(4) + 2
y = 2 + 2
y = 4
Now to graph go on the x axis (horizontal axis) and go to 4, then up 4 on the y axis.
You need to graph the point (4,4).
I hope this helps!
Answer:
see graph (4,4)
to manually graph just pick any two values for X in the first equation and calculate the corresponding Y value ... put a "dot" (a point on the graph)
do for both points , and draw al LINE between them...
repeat fore the second equation... the "solution" is where the two lines cross
Step-by-step explanation:
hello, help needed...again. 35 points !!! please show work for both. thank you:)) due today.
Answer:
16 direct
17 indirect
Step-by-step explanation:
16.
If it is a direct variation
y/x = constant
4/-2 -2
-8/4 = -2
-12/6 = -2
This is a direct variation
17.
y/x = -1/2 /-2 = 1/4
y/x = -1/-1 = 1
This is not a direct variation
If it is an indirect variation then
yx = constant
-1/2 * -2 = 1
-1*-1 =1
3 * 1/3 =1
This is an indirect variation
2. What are the last 2 digits of 1 + 2 + 3 + + 2005 2006
Let S be the sum. So you have
S = 1 + 2 + 3 + … + 2004 + 2005 + 2006
as well as
S = 2006 + 2005 + 2004 + … + 3 + 2 + 1
Then
2S = (1 + 2006) + (2 + 2005) + … + (2005 + 2) + (2006 + 1)
2S = 2007 + 2007 + … + 2007 + 2007
2S = 2006 × 2007
S = (2006 × 2007)/2
S = 2,013,021
which makes the last two digits 21.
half past 9:00p.m. what is half past of 9:00p.m.
Answer:
The answer is 9:30 pm :D.
△ABCis reflected to form △A′B′C′. The vertices of △ABC are A(3, 1), B(1, 5), and C(6, 9). The vertices of △A′B′C′ are A′(−1, −3), B′(−5, −1), and C′(−9, −6). Which reflection results in the transformation of △ABC to △A′B′C′? Reflection across the x-axis reflection across the y-axis reflection across y = x reflection across y=−x I NEED HELP PLS The answer choies are: A. Reflection across the x-axis B. Reflection across the y-axis C. Reflection across y = x D. Reflection across y=−x
Answer: D) reflection across y = -x
Explanation:
When we reflect over y = x, we basically swap x and y. So for instance, the point (3,1) becomes (1,3).
When reflecting over y = -x, we will do the same thing but we'll make each coordinate swap in sign from positive to negative (or vice versa). The rule for reflecting over y = -x is [tex](x,y) \to (-y,-x)[/tex]
So if we apply that rule to point A(3,1) then it becomes A ' (-1, -3).
Similarly, B(1,5) moves to B ' (-5, -1)
Finally, C(6,9) becomes C ' (-9, -6)
Express 0.00506 in standard form
Answer:
[tex]5.06 x 10^{-3}[/tex]
Step-by-step explanation:
Move decimal 3 place to right.
Because the decimal was moved to right, the exponent is negative.
Match each equation with its solution.
Answer:
1. x = -2 , 3
2. x = - 1, 5
3. -1, 6/5
4. - 0/3, 1.3
Step-by-step explanation:
1.
[tex]ln(x+5)=ln(x-1)+ln(x+1)\\\\x+ 5 = (x-1)(x+1)\\\\x + 5 = x^2 - 1\\\\x^2 - x - 6 = 0 \\\\x^2 - 3 x + 2 x - 6 =0 \\\\x(x-3)+2(x-3)=0\\\\x = -2 and 3[/tex]
2.
[tex]e^{x^{2}}=e^{4x +5}\\\\x^2 - 4x - 5 = 0 \\\\x^2 - 5x + x - 5 = 0 \\\\x (x-5)+1 (x-5)=0\\\\x = -1 and 5[/tex]
3.
[tex]log_{4}(5x^2 +2)=log_{4}(x +8)\\\\5x^2 - x - 6 = 0 \\\\5 x^2 - 6 x + 5x- 6 = 0 \\\\5 x (x + 1)-6(x+1)=0\\\\x = -1 and \frac{6}{5}[/tex]
4.
[tex]log(x-1)+log 5x = 2\\\\5 x (x-1) =2 \\\\5x^2 - 5x -2 = 0 \\\\x = \frac{5\pm\sqrt{25+40}}{10}\\\\x = \frac{5\pm 8}{10}\\\\x = 1.3, - 0.3[/tex]
In a triangle ABC, angle BAC = 53° and angle ACB = 28°. If AB is produced to D, find angle CBD.
Angle CBD= 81°
I hope it helps you...
Answer:
81
Step-by-step explanation:
∠CBD is the exterior angle of the ΔABC.
Exterior angle property:
Exterior angle equals the sum of opposite interior angles.
∠CBD = ∠ABC + ∠ACB
= 53 + 28
= 81°
Find square root of 0.0324
Answer:
0.18
Step-by-step explanation:
If there were 36 candies and only 12 children, how many candies would each child get?
Answer:
3 each
Step-by-step explanation:
36 / 12 = 3
.................................................
PLEASE HELP ME! I REALLY NEED HELP
Answer:
a)
(i) 5.8 hours
(ii) 6.5 hours
(iii) 6 hours
(iv) 6 hours
b) 180 hours
Captain Liz is going to load her cruise ship with bags of sugar. She has room for 19 bags of sugar. She has allotted for 121 pounds of sugar on her ship. She can choose from 7-pound bags (the variable s) or 10-pound bags (the variable p). Which equations would be a constraint to Captain Liz maximizing her sugar load?
Correct answers with explanations will earn you brainliest :)
Answer:
[tex]19 = s + p[/tex] and [tex]121 = 7s + 10p[/tex]
Step-by-step explanation:
First we use constraints given by the problem to set up two equations:
We can only have a total of 19 bags, so:
[tex]19 = s + p[/tex]
Then, we want to maximize her sugar load. Using the info on the weight of each bag and the max carrying capacity:
[tex]121 = 7s + 10p[/tex]
Answer:
Step-by-step explanation:
Let the sugar from 7 pound bags be represented by = s
And let the sugar from 10 pound bags be represented by = p
As given, Captain Liz has room for 19 bags of sugar.
This becomes [tex]s+p=19[/tex] .......(1)
Also given is , she has room for 19 bags of sugar, so equation becomes:
[tex]7s+10p=121[/tex] ............(2)
Hence, these are the correct equations.