13X squared + 7X + 12
7x-x2 = x(7-x)
x(x-7)
If you mean: x squared -7x +12 then it is (x-3)(x-4) when factored
Factorise it: (x + 5)(3x - 8)
5x2+7x = 12 5x2+7x-12 = 0 (5x+12)(x-1) = 0 x = -12/5 or x = 1
x^2+7x-30 = (x-3)(x+10)
(x - 5)(x + 12)
It is (x+3)(x+4) when factored
7x2+49x-42 = 7(x2+7x-6)
(x + 11)(x - 4)
It is: x(x-3) factorized