SOLUTION: Put the following quadratic equations into vertex form f(x)=-4x^2-18x+5

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Question 1002668: Put the following quadratic equations into vertex form
f(x)=-4x^2-18x+5
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
y=-4x^2-18x+5
y-5=-4(x^2+9x/2)
Complete the square
y-5= -4(x^2+(9x/2)+81/16)+(81/4), subtracting (-4)(81/16) from one part, must add it back.
y= -4{x+(9/2)^2}+25(1/4)
check by the vertex h=-b/2a and k=f(h). Vertex x=value is 18/-8=-2.25, and the y-value is 25.25

graph%28300%2C200%2C-10%2C10%2C-25%2C30%2C-4%28x%2B%289%2F2%29%29%5E2%2B25.25%29