Question

3) How long does it take the apple to reach your friend?
(**HINT: The time would be the x-coordinate of the highest point.)

Double click on the space below to show your work.

h(t) = – 16t2 + 38.4t + 0.96

H= Height. T= Time (seconds).

I WILL FAN AND MEDAL FOR ANSWERS AND WORK.

Answer 1

Set the equation = 0. Then use quadratic formula.

Answer 2

It is supposed to be h(t) = -16t^2 + 38.4t + 0.96

Answer 3

Ok! Set the equation = 0.

Answer 4

\(\huge -16t^2+38.4t+0.96=0\)

Answer 5

Do you know the quadratic formula?

Answer 6

Then it would be \[-38\pm \sqrt{38.4^{2}-4(-16)(0.96)} / 2(-16)\]

Answer 7

Right?

Answer 8

@mathway

Answer 9

The beginning is supposed to be -38.4 not just -38.

Answer 10

Yes! Now solve for t. :) And since it is time, your answer shouldn't be the negative one.

Answer 11

Let me know if you got an answer, so I may check if it's right. :)

Answer 12

So then I get: \[-38.4\pm \sqrt{1,536} / -32\] I'm confused on what to do after this step.

Answer 13

\(\huge \frac{-38.4±\sqrt {1536}}{-32}\)

Frind the square root of 1536 first.

Answer 14

\[16\sqrt{6}\]

Answer 15

\(\huge \frac{-38.4±16\sqrt {6}}{-32}\rightarrow\) \(\huge \frac{-38.4+16\sqrt {6}}{-32} \) & \(\huge \frac{-38.4-16\sqrt {6}}{-32} \)

Answer 16

Should it be in radical form or could it be in decimal form?

Answer 17

So how do we get the answer from there? It should be in decimal form since we are trying to find how many seconds it takes the apple to reach your friend.

Answer 18

Great! Now get a calculator and solve for it. Notice that \(\sqrt{6} =2.45\).

Answer 19

\(\huge \frac{-38.4+16(2.45)}{-32}\) &\(\huge \frac{-38.4-16(2.45)}{-32}\)

Answer 20

Still confusing?

Answer 21

I got -0.02

Answer 22

Or should it be positive 0.02? @mathway

Answer 23

You're supposed to get \(\huge \color{red}{ \text{TWO}}\) solutions. and \(-0.02\) is one. And since it is negative, it can't be the time. So solve for the other one.

Answer 24

2.4 seconds rounded.

Answer 25

Correct! :)

Answer 26

Thank you so much!!!

Answer 27

No problem! :)