a) a + b + c = 14 + 25 = 39
b) a + 3b + 3c = a + 3(b + c) = 14 + 3 * 25 = 14 + 75 = 89
c) 5a + 2c + 2b = 5a + 2(b + c) = 5 * 14 + 2 * 25 = 70 + 50 = 120
d) ab + ac + 5a - 16b - 16c = a(b + c) + 5a - 16(b + c) = 14 * 25 + 5 * 14 - 16 * 25 = 350 + 70 - 400 =
420 - 400 =
20