Question

Jared is casting his fishing line with a lead sinker attached over the edges of a pier. The pier is 15 feet above the water. The function h = -16² +15 gives the sinker's height h above the water (in feet) after t seconds. Graph the function. How many seconds does it take for the sinker to hit the water?​

Answer 1

To find how long it takes for the sinker to hit the water, we need to solve the equation h = -16t^2 + 15 for t when h = 0. This is because the sinker will hit the water when its height above the water is zero.

-16t^2 + 15 = 0

16t^2 = 15

t^2 = 15/16

t = ± √(15/16)

We ignore the negative value of t because time cannot be negative in this context. Therefore:

t = √(15/16) ≈ 0.97 seconds

So it takes approximately 0.97 seconds for the sinker to hit the water.