The completed square form is x^2 −6x−8x=(x−7)^2−49
To complete the square for the quadratic expression x^2 −6x−8x, follow these steps:
Factor out the coefficient of x^2 , which is 1:
x^2 −6x−8x=x^2 −14x
Take half of the coefficient of x (in this case, −14/2=−7) and square it (−7)^2 =49).
Add and subtract the result from step 2 inside the parentheses:
x^2 −14x+49−49
Now, you can express the quadratic expression as a perfect square trinomial and a constant term:
x^2 −14x+49−49=(x−7)^2 −49
So, the completed square form is x^2 −6x−8x=(x−7)^2−49