You don't. 51 is a Prime number, so this expression can not be factored.
x2-14 does factor but not pretty; it factors to: (x+sqrt14)(x-sqrt14).
x2 - 14 = 51 so x2 = 65 and then x = +/- sqrt(65) = +/- 8.06
(x - 1)(x - 14)
14
51 > 0. Since the sum 14 is positive, the factors of 51 are both positive. The problem is that 51 = 3*17 and 3 + 17 = 20 ≠ 14. But we are lucky that 14 = 7 + 7. So wee can use the difference of the squares such as (7 - A)(7 + A) = 49 - A2 = 51, where -A2 = 2 = -(i√2)2 . Thus, the numbers are 7 - i√2 and 7 + i√2. or algebraically, x + y = 14; y = 14 - x xy = 51 x(14 - x) = 51 -x2 +14x = 51 x2 -14x = -51 x2 -14x + 72 = -51 + 49 (x - 7)2 = -2 x - 7 = ± √-2 x = 7 ± i√2
14
(x+7)(x+2)
(x - 14)(x - 2)
x2-x=x(x-1)
9 - x2 will factor into (3 - x)(3 + x)
-(x - 7)(x + 2)
7x2 + 7x - 14 = 7(x2 + x - 2) = 7(x + 2)(x - 1)