Question

a person walking across a bridge accidentally drops an orange into the river below from a height of 40 ft. the function h= -16t^2+40 gives the orange'a approximate height h above the water, in feet, after t seconds. graph the function. in how many seconds will the orange hit the water?

Answer 1

1.58113883 seconds

Explanation:

h= -16t^2+40

We want to find when h = 0, or when the orange hits the water

0 = -16t^2+40

Subtract 40 from each side

-40 = -16t^2+40-40

-40 = -16t^2

Divide by -16

-40/-16 = -16/-16 t^2

2.5 = t^2

Take the square root of each side

±sqrt(2.5) = sqrt(t^2)

±1.58113883 = t

Now time can only be positive (it can't hit the water before it is dropped),

so t= 1.58113883 seconds