X=4.2666666666667
In 7x+7, x is a variable.
7x-2
x^2 +7x+12 = (x+3)(x+4) when factored
x^2 +7x+6 = (x+1)(x+6) when factored
7x
7x/3 = 105 7x = 315 x = 45
x2 + 7x + 6 = (x + 6) (x + 1)
6x+x=7x
7x-4=x+2 7x=x+2+4 7x=x+6 7x-x=6 6x=6 X=1
7x+17 = 45 7x = 45-17 7x = 28 x = 4
x2 + 7x - 8 = (x + 8)(x - 1)