Final answer:
To transform the equation (x-6)(x+2)=9 by completing the square, first expand the equation, move constant term, add square of half the coefficient of x to both sides, and simplify to get (x-2)^2=25.
Step-by-step explanation:
To transform the equation (x-6)(x+2)=9 by completing the square, first expand the equation:
x^2 - 4x - 12 = 9
Now, move the constant term to the right side:
x^2 - 4x - 21 = 0
To complete the square, add the square of half the coefficient of x to both sides:
x^2 - 4x + 4 - 21 = 4
This simplifies to:
(x-2)^2 = 25
So, the resulting equation is (x-2)^2=25. Therefore, the correct answer is (A) (x-2)²=25.