Question

Check my answer for medal + Fan

Answer 1

My answer : 4
Which statement best describes the graph of -x3 - x2 + 4x + 4?

1) It starts down on the left and goes up on the right and intersects the axis at x = -2, 2, and 4.
2) It starts down on the left and goes up on the right and intersects the axis at x = -2, -1, and 2.
3) It starts up on the left and goes down on the right and intersects the x-axis at x = -2, -1, and 2.
4) It starts up on the left and goes down on the right and intersects the axis at x = -2, 2, and 4.

My answer : -158
A ball is thrown upward from the top of a building. The function below shows the height of the ball above the ground, f(t), in feet, at different times (t) in seconds:
f(t) = -16t2 + 34t + 80

The average rate of change of f(x) from x = 5 to x = 7 is _____.

Answer 2

No need for medal and fan, just ask.

Answer 3

what are the roots?

Answer 4

-2, -1, and -2 right?

Answer 5

Okay, so you ca already predict that it goes down on the left, because the coefficient of the largest term is negative.
The degree is 3, so you will have something like

••• •
• • •
• • •
• •••

Answer 6

So at the right end it will go up.

Answer 7

i see... so it would be nubmer 1 not 4

Answer 8

And the roots are
\(\normalsize\color{black}{ -x^3 - x^2 + 4x + 4}\)\(\LARGE\color{white}{ \rm │ }\)
\(\normalsize\color{black}{ -x^2(x + 1) + 4(x + 1)}\)\(\LARGE\color{white}{ \rm │ }\)
\(\normalsize\color{black}{ (-x^2+4)(x + 1) }\)\(\LARGE\color{white}{ \rm │ }\)
\(\normalsize\color{black}{- (x^2-4)(x + 1) }\)\(\LARGE\color{white}{ \rm │ }\)
\(\normalsize\color{black}{- (x-2)(x+2)(x + 1) }\)\(\LARGE\color{white}{ \rm │ }\)

\(\normalsize\color{black}{2,~~-2,~~-1 }\)\(\LARGE\color{white}{ \rm │ }\)

Answer 9

So you know that \(\normalsize\color{black}{ x→∞,~~y→∞}\) and \(\normalsize\color{black}{ x→~-∞,~~y→~-∞}\) .
And roots are \(\normalsize\color{black}{ 2,~~-2,~~-1}\)

Answer 10

Which option do you choose, @NoCopsForMiles

Answer 11

2

Answer 12

Yes !

Answer 13

thank you for your help

Answer 14

Anytime!

Answer 15

2)
A plot is attached.

Answer 16

My answer : -158
A ball is thrown upward from the top of a building. The function below shows the height of the ball above the ground, f(t), in feet, at different times (t) in seconds:
f(t) = -16t2 + 34t + 80

The average rate of change of f(x) from x = 5 to x = 7 is _____.

Answer 17

f(t) = -16t² + 34t + 80

`f(5)` = -16(5)² + 34(5)+ 80= `-150`

`f(7)` = -16(7)² + 34(7) + 80= `-466`

So from x=5, to x=7, you moved 316, and to the negative direction.

So the average rate would be, 158.

CORRECT !

Answer 18

you were right, -158 :)
Next time though, please try to ask 1 question per thread. ty, and yw !

Answer 19

-158
A Mathematica solution is attached.