Factor each trinomial mentally x^2 -8x + 7 = (x-1)*(x-7) x^2 -6x - 7 = (x-7)*(x+1) x^2 +7x + 6 = (x+1)*(x+6) x^2 -x - 42 = (x-7)*(x+6) Then write your expression as the product of fractions and make all necessary reductions. As simple as 2 x 2 = 4.