SOLUTION: The range of this equation -20x(squared)+10x+6

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: The range of this equation -20x(squared)+10x+6      Log On


   

Question 373451: The range of this equation -20x(squared)+10x+6
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
Range means all possible values of y or f(x). Here we have a parabola, concave down...its vertex will be a maximum value...
For y+=+-20x%5E2+%2B+10x+%2B+6,
the value where x = -b/2a gives you the x coordinate of the max value...here that is
x = -10/-40 = 1/4
Plugging this into the equation, we get
-20(1/4)^2 + 10(1/4) + 6 =
-20/16 + 2.5 + 6 =
-1.25 + 8.5 =
7.25