Asked by Massudi
A football is punted. Its height, H metres is given by the quadratic relation with equation: H = -5t^2 + 21t, where t is the time in seconds after the punt.
Algebraically determine the maximum height of the football. Show all of your steps.
Algebraically determine the maximum height of the football. Show all of your steps.
Answers
Answered by
oobleck
again, you want the vertex.
-5t^2 + 21t
= -5(t^2 - 21/5 t + (21/10)^2) + 5(21/10)^2
= -5(t - 21/10)^2 + 441/20
so the max height is 441/20 meters
or, we know the vertex is midway between the roots of 0 and 21/5
so find h(21/10) = 441/20
-5t^2 + 21t
= -5(t^2 - 21/5 t + (21/10)^2) + 5(21/10)^2
= -5(t - 21/10)^2 + 441/20
so the max height is 441/20 meters
or, we know the vertex is midway between the roots of 0 and 21/5
so find h(21/10) = 441/20