Answer:
x = 2 ±√7
Step-by-step explanation:
Given in the question an expression,
3x² -12x = 9
Let's assume that the expression can be factored as the perfect square (x+a)²
This expression is expanded as x²+2ax+a²
divide by 3
3x²/3 -12x/3 = 9/3
x² - 4x = 3
Add completing the square
2ax = -4x
a = -2
a² = 4
x² - 4x +4= 3+4
x² - 4x + 4 = 7
(x-2)² = 7
(x-2)² = 7
√(x-2)² = √7
x-2 = √7
x = 2 ±√7
