Question

MEDALSSS!!!
13. A ball is thrown into the air. The height in feet of the ball can be modeled by the equation h = -16t2 + 20t + 6 where t is the time in seconds, the ball is in the air. When will the ball hit the ground? How high will the ball go?

Answer 1

Set h(t) = 0 to find when the ball will hit the ground
You should get t = 1.5 (t has to be positive)

The max height occurs at the vertex at the parabola which is on the axis of symmetry.
Axis of symmetry = \[-b/2a=-20/-32=5/8\]. Plug this value into h(t) to obtain the vertex which is (0.625,12.25).

Answer 2

okk

Answer 3

You can see that you evidently have a quadratic equation so may use the quadratic formula to solve for the "positive' value

Answer 4

so i divide or multiply

Answer 5

@Johnbc

Answer 6

@gaberen

Answer 7

Divide or multiply what?

Answer 8

use the quanratic formula, or complete the square , set h=0 and u have to solve for t

Answer 9

because your motion is described by a negative parabola, so there will be 2 points when height =0 once when its launched and when it hits the ground again

Answer 10

you want that 2nd longer time