Answer:
Choice d is the answer.
Explanation:
We have given a equation.
(x-12)(x+4) = 9
We have to find the solution using completing square technique.
Simplifying given given equation, we have
x²+4x-12x-48 = 9
Adding 48 to both sides of above equation, we have
x²-8x-48+48 = 9+48
x²-8x = 57
Adding the square of half of the term -8x to both sides of above equation, we have
x²-8x+(-4)² = 57+(-4)²
x²+2(1)(-4)+(-4)² = 57+16
(x-4)² = 73
Taking square root to both sides of above equation, we have
√(x-4)² = √73
x-4 = ±√73
Adding 4 to both sides of above equation, we have
x-4+4 = ±√73+4
x = 4±√73 which is the answer.