Okay so basically, you subtract 18 on both sides since the 18 doesn't work, making the equation x² - 10x = -18 So then you add (b/2)², which is 25, to both sides, to get x² - 10x + 25 = 7 After this, you factor. (x-5)(x-5) = 7 Then you simplify. (x-5)² = 7 Then you solve for x. √(x-5)² = √7 x-5 = (+ or -)√7
