Question

Evaluate the following, using suitable property.
a) 39 × 97
c) (– 85) × 43 + 43 × ( – 15) e) 53 × (-18)
g) x 79
b) 68 × (–17) + 68 × (−3) d) 18946 × 99 – (–18946) f) 125 x 53 x
h) 15 × (–99)

Answer 1

Answer:

(i) -39 × 99 = -39 × [100 -1] = -39 × 100 + (-39) × (-1) = -3900 + 39 = -3861 (ii) (-85) × 43 + 43 × (-15) = 43 × (-85) + 43 × (-15) = 43 × [-85 – 15] = 43 × [-100] = -4300 (iii) 53 × (-9) – (-109) × 53 = 53 × (-9) – 53 × (-109) = 53 × [(-9) – (-109)] = 53 × [-9 + 109] = 53 × 100 = 5300 (iv) 68 × (-17) + (-68) × 3 = 68 × (-17) + 68 × (-3) = 68 × [(-17) + (-3)] = 68 × (-20) = -1360

Step-by-step explanation: