x² - 11x + 18
find factors of x² and 18 that will give you -11x
x² - 11x + 18
x -9
x -2
(x - 9)(x -2) is your answer
if you are finding the x, place each parenthesis equal to zero
x - 9 = 0
x - 9 (+9) = 0 (+9)
x = 9
x - 2 = 0
x - 2 (+2) = 0 (+2)
x = 2
x = 2, 9
hope this helps