Answer:
(x - 10)(x - 2) = 0, x = 10, 2
Explanation:
x² - 12x = -20
Add 20 to both sides.
x² - 12x + 20 = 0
To complete the square, find values that add up to the middle coefficient and multiply to the final number. In this case, -10 and -2 add to -12 and multiply to 20.
(x - 10)(x - 2) = 0
Now solve each individual pair.
x - 10 = 0
x = 10
x - 2 = 0
x = 2