SOLUTION: need help write the function f(x)=-5xSquared -60x-181 in vertex form and identify its vertex

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Question 384955: need help write the function f(x)=-5xSquared -60x-181 in vertex form and identify its vertex
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

the vertex form of a parabola: y=a%28x-h%29%5E2+%2Bk where(h,k) is the vertex

f(x) = -5x^2 - 60x - 181   Completing the square

f(x) = -5(x^2 + 12x) - 181

f(x) = -5[(x + 6)^2 -36] - 181

f(x) = -5(x + 6)^2 + 180 - 181

f(x) = -5(x + 6)^2 -1

Vertex is Pt (-6,-1)  Note: parabola opens downward as a < 0

graph%28+300%2C+300%2C-10%2C10%2C-10%2C10%2C-5x%5E2+-+60x+-+181%29+