Question 630440: A person standing close to the edge on top of a 192-foot building throws a baseball vertically upward. The quadratic function s(t)=-16t2+64t+192 models the balls’ height above the ground, s(t() in feet, t seconds after it was thrown. After how many seconds does the ball reach its maximum height? Round to the nearest tenth of a second if necessary.
Answer by nerdybill(7384)   (Show Source):
You can put this solution on YOUR website! A person standing close to the edge on top of a 192-foot building throws a baseball vertically upward. The quadratic function s(t)=-16t2+64t+192 models the balls’ height above the ground, s(t() in feet, t seconds after it was thrown. After how many seconds does the ball reach its maximum height? Round to the nearest tenth of a second if necessary.
.
Since:
s(t)=-16t2+64t+192
is a polynomial of degree 2, we know it is a parabola. We also know that it opens downward (based on the negative coefficient associated with the x^2 term). The vertex must then represent the maximum.
"axis of symmetry" represents the max time of vertex:
t = -b/(2a)
t = -64/(2(-32))
t = -64/(-64)
t = 1.0 seconds
|
|
|
