SOLUTION: what is the equation of the quadratic function with roots -9 and and -3 and a vertex at (-6, -1).

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: what is the equation of the quadratic function with roots -9 and and -3 and a vertex at (-6, -1).       Log On


   



Question 391027: what is the equation of the quadratic function with roots -9 and and -3 and a vertex at (-6, -1).


Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!

Hi,
Parabola with vertex at pt(-6,-1) and x-intercepts are (-9,0) and (-3,0)
Using the vertex form of a parabola, y=a%28x-h%29%5E2+%2Bk where(h,k) is the vertex
y = a(x+6)^2 - 1 Using Pt(-3,0) to solve for a
0 = a *3^2 - 1
1 = 9a
1/9 = a
y = 1/9(x+6)^2 - 1