SOLUTION: f(x)=-2x^2+6x how many seconds will it take the ball to reach the maximum height

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: f(x)=-2x^2+6x how many seconds will it take the ball to reach the maximum height      Log On


   

Question 1098986: f(x)=-2x^2+6x
how many seconds will it take the ball to reach the maximum height
Found 2 solutions by Fombitz, Boreal:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Convert to vertex form,
f%28x%29=-2%28x%5E2-3x%29
f%28x%29=-2%28x%5E2-3x%2B%283%2F2%29%5E2%29%2B2%283%2F2%29%5E2
f%28x%29=-2%28x-3%2F2%29%5E2%2B9%2F2
The max height occurs at the vertex at t=3%2F2

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
-2x^2+6x=0
The vertex x-value is -b/2a. This is -6/-4 or 1.5 seconds, to the vertex, which is the maximum height.
graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C-2x%5E2%2B6x%29