Question

Q11

A ball is thrown vertically upward. After t seconds, its height, h (in feet), is given by the function h left parenthesis t right parenthesis equals 76 t minus 16 t squared. After how long will it reach its maximum height?

Round your answer to the nearest hundredth.

Group of answer choices

90 seconds

1.2 seconds

0.17 seconds

2.38 seconds

Answer 1

Explanation:

To find when the ball reaches its maximum height, we need to find the vertex of the quadratic function h(t) = 76t - 16t^2.

The vertex of a quadratic function of the form y = ax^2 + bx + c is at the point (-b/2a, f(-b/2a)), where f(x) = ax^2 + bx + c.

In this case, a = -16 and b = 76, so the time at which the ball reaches its maximum height is given by:

t = -b/2a = -76/(2*(-16)) = 2.375

Rounded to the nearest hundredth, the ball reaches its maximum height after 2.38 seconds (Option D).