Which of the following is equivalent to f(x)=-x^2-6x+2 ?
a) f(x)=-(x+3)^2-7
b) f(x)=-(x-3)^2-7
c) f(x)=-(x-3)^2+11
d) f(x)=-(x+3)^2+11
-f(x)= +x^2 + 6x -2
-f(x) + 2 = x^2 + 6x
now complete the square by adding (6/2)^2 to both sides
-f(x) + 2 + 9 = x^2 + 6x + 9
-f(x)+ 11 = (x+3)^2
-f(x) = (x+3)^2 -11
so
f(x) = -(x+3)^2 + 11