Question

Rewrite the function by completing the square. f ( x ) = x 2 − 8 x − 51 f(x)=x 2 −8x−51

Answer 1

(x-4)^2 - 67

Explanation:

f ( x ) = x^ 2 − 8 x − 51

Take the coefficient of x

-8

Divide by 2

-8/2 = -4

Square it

(-4)^2 = 16

Add this and subtract it

f ( x ) = x^ 2 − 8 x +16 -16− 51

= (x^2 -8x+16) - 67

= (x-4)^2 - 67