Question

Find: (a) 15 × (–16) (b) 21 × (–32) (c) (– 42) × 12 (d) –55 × 15 2. Check if (a) 25 × (–21) = (–25) × 21 (b) (–23) × 20 = 23 × (–20)

Answer 1

a) -240

b) -672

c) -504

2.

a) Yes , as 25 × (–21) = -525 and (–25) × 21 = -525

b) Yes , as (–23) × 20 = -460 and 23 × (–20)= -460

both are proved using commutative Property of multiplication.