Quadratic Equation Question

Question

You throw a stone off a cliff 36 feet above the water. The height of the stone in terms of time in seconds is given by h(t)= -16t²+7t+36. At what time will the stone splash into the water?

Answer 1

We know from looking at the equation that at time = 0, height = 36.

So, the stone hits the water when h(t) = 0, this happens when

-16t² + 7t + 36 = 0 Using the quadratic equation we find that

x = -1.297 and 1,735 since the negative number is not realistic

x = 1.735 seconds