Question

When Annie hits a softball, the height of the

ball above the ground after t seconds is given
by h = -4.9/2 + 19.61 + 1.4 metres. Find the
maximum height reached by the ball.

Answer 1

21 metres.

Explanation:

I think you mean the equation to be:

h = -4.9t^2 + 19.6t + 1.4

To find the maximum height we convert the equation to vertex form:

h = -4.9(t^2 - 4t) + 1.4

h = -4.9[(t - 2)^2 - 4] + 1.4

h = -4.9(t - 2)^2 + 19.6 + 1.4

h = -4.9(t - 2)^2 + 21.

The maximum height is 21 metres.