Question 834767
A football is kicked into the air.  The equation h=-4.9t(to the power of)2 + 9.8t + 1 expresses the relationship between height (h) and time (t), in seconds.

a. Determine the maximum height reached by the football.
-------------
h(t) = -4.9t^2 + 9.8t + 1
It's a parabola.  The max ht is the vertex.  The vertex is at
t = -b/2a = -9.8/-9.8 = 1 second
h(1) = 5.9 meters
---------------------------
b. At what time after the kick is the ball at a height of 5m.
h(t) = -4.9t^2 + 9.8t + 1 = 5
Solve for t.  There are 2 values, one going up, one falling.