Answer :

looks like the first thing you have to find is their GCF, ya reckon ? The factors of  56  are  1, 2, 4, 7, 8, 13, 28, and 56 . The factors of  64  are  1, 2, 4, 8, 16, 32, and 64 . The common factors are  1, 2, 4, and 8 . The greatest one is  8 . 56/8 = 7 64/8 = 8 56  plus  64 = (8 times 7)  plus  (8 times 8) 56  plus  64 =  8 times (7 plus 8)    <== that's the answer Check it out: 56  plus  64 = 120 8 times (7 plus 8) = 8 times 15 = 120    yay!