When a ball is thrown in the air, the height h of a ball in feet t seconds after the ball is thrown in the air, is given by the equation height = 25t–16t²

Use the quadratic equation to determine how many seconds goes by before the ball hits the ground?

1 answer

When the ball hits the ground height be zero.

25 t - 16 t ^ 2 = 0

t ( 25 - 16 t ) = 0

This equation will be zero when t = 0

OR

25 - 16 t = 0

25 - 16 t = 0 Add 16 to both sides

25 - 16 t + 16 t = 0 + 16 t

25 = 16 t Divide both sides by 16

25 / 16 = t

t = 25 / 16

When t = 0 ball does not fly.

So solution are :

t = 25 / 16 seconds