Find the sum of ∑4/k=1 (-4k)

Answer:

each movie costs $2.75, each video game costs $6.75

Step-by-step explanation:

x = movies, y = video games

7x + 9y = 80

5x + 3y = 34

simplified to

x = 11/4 , y = 27/4

Answer:

A

Step-by-step explanation:

The correct answer is A

Answer:

There are two intersections.

(-3,1) and (-1,-3)

Step-by-step explanation:

Answer:

They intersect at (-3,1), and also (-1,-3)

Step-by-step explanation:

Graph:

9514 1404 393

Answer:

  (b)  f(x) = (-x)^(1/2)

Step-by-step explanation:

The square root is only defined for argument values that are non-negative. Hence the domain of ...

  f(x) = (-x)^(1/2)

is all values of x less than or equal to zero. This is not "all values of x."

Answer:

can you please send me another one

Answer:

2.1n-2.1

Step-by-step explanation:

The increase is

1.10 (n-1)= 1.1n -1.1

Add this to the original amount

(n-1) + 1.1n - 1.1

2.1n-2.1

Answer:

(0.123 ; 0.277)

Step-by-step explanation:

Given :

Sample size, n = 180

x = 36

Proportion, p = x / n = 36/180 = 0.2

Confidence interval for sample proportion :

Confidence interval :

p ± Zcritical * √p(1 - p) / n

Zcritical at 99% = 2.576

0.2 ± 2.576 * √0.2(1 - 0.2) / 180

0.2 ± 2.576 * 0.0298142

0.2 ± 0.0768013792

(0.123 ; 0.277)

Step-by-step explanation:

The answer is 5/8 + 1/3

Answer = 5*3 /(8*3) +8/24 =23/24

Answer = 23/24

Answer:

[tex]{ \tt{m.n = |m| |n| \cos( \theta) }} \\ { \tt{ (3 \times 2) + (4 \times - 1) = (5)( \sqrt{5}) \cos( \theta) }} \\ { \tt{ \cos( \theta) = \frac{0.4}{ \sqrt{5} } }} \\ \theta = 79.7 \degree[/tex]

Answer:

$150

Step-by-step explanation:

discount=60%

let the price=x

(100-60)% of x=$60

40% of x=60

x=60×(100/40)=150

Answer:  Choice A.   [tex]-x^2+2x+8[/tex]

Work Shown:

[tex](f - g)(x) = f(x) - g(x)\\\\(f - g)(x) = (2x+1) - (x^2-7)\\\\(f - g)(x) = 2x+1 - x^2+7\\\\(f - g)(x) = -x^2+2x+(1+7)\\\\(f - g)(x) = -x^2+2x+8\\\\[/tex]

which shows the answer is choice A.

Side note: be sure to distribute the negative to every term inside the second set of parenthesis. So you wouldn't say -(x^2-7) = -x^2-7. If you did this error, then you'd get to the wrong answer choice C.

Answer:

hope it helps u plz mark me brainliest mate

Step-by-step explanation:

(f-g)(x)=2x+1-(x^2-7)

(f-g)(x)=2x+1-x^2+7

(f-g)(x)= -x^2+2x+8

this is the correct answer

Answer:

10.5

Step-by-step explanation:

In the picture if you think about it, it has to be a number less than 15 since CB is 15. I picked 12.3 and got it wrong therefore it has to be 10.5.

Answer:

A) 10.5

Step-by-step explanation:

Answer:

Speed of canoiest is 10 miles/hour.

Speed of current is 2 miles/hour.

Step-by-step explanation:

Let the speed of canoiest is v and the speed of current is u.

distance = speed x time

24 = (v + u ) x 2

v + u = 12 ..... (1)

Now

24 = (v- u) x 3

v - u = 8 .... (2)

By solving (1) and (2)

2 v = 20

v = 10 miles/hour

u = 2 miles/hour

Answer:

3

Step-by-step explanation:

Given the data:

1405, 1121, 1339, 1096, 1299, 1401, 1138, 1149, 1223, 1071, 1399, 1400, 1242, 1318, 1101, 1065, 1428, 1225, 1350, 1358, 1312

Using the intervals:

Class interval ___ Frequency

1049–1118 ________ 4

1119–1188 ________ 3

1189–1258 ________3

1259–1328 _______ 3

1329–1398 _______ 3

1399–1468 _______ 5

From the table ; the fifth class is the interval :

1329 - 1398 and it has a frequency of 3

Answer: welcome to brainly

Step-by-step explanation:

Hello there! My name is agenthammerx, a Master Answerer and Engagement Team Member here on Brainly. I am here to welcome you to the site! Thank you for taking initiative to check out Brainly and for posting your first question! The Brainly Community welcomes you. If you have any questions regarding anything about the site, please don’t hesitate to reach out to me! I will try my best to help you and answer your question or check out our help center at https://faq.brainly.com/

Answer:

25.987957

Step-by-step explanation:

y=-4x²-8x+1

а<0 so we will be looking for maximum

х=-b/2a=8/-8=-1

у=4+8+1=13

Maximum point (-1;13)

Answer:

D. 9n = 27

Step-by-step explanation:

If we need one adult for every 9 students, we can represent that as 9n:

if n is the number of adults.

Because we have 27 students, the equation 9n = 27 works.

A better way of formatting the equation is:

n = 27/9

Because it directly shows what the number of adults is, but with some reformatting, it is clearly the same equation.

Answer:

D) 13

[tex]\sqrt{169} = 13[/tex]

Step-by-step explanation:

Answer:

7

Step-by-step explanation:

Answer:

7

Step-by-step explanation:

Starting from right to left...

9 is in the ones place

8 is in the tenths place

4 is in the hundreds place

7 is in the thousands place.

I hope this helps!

Answer: [tex]y^\frac{1}{8}[/tex]

Step-by-step explanation:

Ok so when taking roots the number in the little corner at the left of the radical sign (if there is one) is the root you take. It could be the 4th root, 6th root, or the x root. You don't have to use the radical sign though, you can use an exponent to write it. All you have to do is take the reciprocal of the number to find what to write for the exponent. So for those examples it would be [tex]\frac{1}{4}, \frac{1}{6} ,\frac{1}{x}[/tex]. The number in the top left of the radical sign is 8 so the answer would be [tex]y^\frac{1}{8}[/tex]

Answer:

5×789/3

Step-by-step explanation:

According to the question you could simplify the above numbers .

Answer:

789

Step-by-step explanation:

let the number=x

[tex]\frac{5x}{3}=1315\\5x=1315 \times 3=3945\\x=\frac{3945}{5}=789[/tex]

Answer:

Harry collected 180 stamps

Harry's sister collected 60 stamps

Step-by-step explanation:

Let X be the number of stamps that Harry's sister colleted.

The number of stamps Harry colleted is 3 time as many as his sister's

⇒ 3*X + X = 240

⇒ X = 60

⇒ 240 - 60= 180

Answer:

180 for harry and 60 for his sister

Step-by-step explanation:

Answer: 12

Step-by-step explanation:

Answer:

12

Step-by-step explanation:

Check the picture below

f(5) = -50

Hope it helps you...

"no terms independent of x" basically means there is no constant term, or the coefficient of x ⁰ is zero.

Recall the binomial theorem:

[tex]\displaystyle (a+b)^n=\sum_{k=0}^n\binom nk a^{n-k}b^k[/tex]

So we have

[tex]\displaystyle \left(1+ax^2\right)\left(\frac2x-3x\right)^6 = \left(1+ax^2\right) \sum_{k=0}^6 \binom 6k \left(\frac2x\right)^{6-k}(-3x)^k[/tex]

[tex]\displaystyle \left(1+ax^2\right)\left(\frac2x-3x\right)^6 = \left(1+ax^2\right) \sum_{k=0}^6 2^{6-k}(-3)^k\binom 6k x^{2k-6}[/tex]

[tex]\displaystyle \left(1+ax^2\right)\left(\frac2x-3x\right)^6 = \sum_{k=0}^6 2^{6-k}(-3)^k\binom 6k x^{2k-6}+a\sum_{k=0}^6 2^{6-k}(-3)^k\binom 6k x^{2k-4}[/tex]

The first sum contributes a x ⁰ term for 2k - 6 = 0, or k = 3, while the second sum contributes a x ⁰ term for 2k - 4 = 0, or k = 2. The coefficient of the sum of these terms must be zero:

[tex]2^{6-3}(-3)^3\dbinom 63 + a\times2^{6-2}(-3)^2\dbinom 62 = 0[/tex]

which reduces to

2160a - 4320 = 0

2160a = 4320

a = 2

Answer:

yefeihuerijohiftv3ugrhoerfujfy

Step-by-step explanation: