46+а+24+а; 25×9×b×4; 96a+4а; 57+b+43+b; 89m-9m; 72n+28n.

46 + а + 24 + а = (а + а) + (46 + 24) = 2а + 70
25 * 9 * b * 4 = (25*4*9) * b = (100*9) * b = 900b
96а + 4а = (96 + 4) * а = 100а
57 + b + 43 + b = (b + b) + (57 + 43) = 2b + 100
89m - 9m = (89 - 9) * m = 80m
72n + 28n = (72 + 28) * n = 100n