Multiply: i. 16xy × 18xy ii. 23xy2 × 4yz2 iii. (12a + 17b) × 4c�

1.	Multiply: i. 16xy × 18xy ii. 23xy2 × 4yz2 iii. (12a + 17b) × 4c iv. (4x + 5y) × (9x + 7y)
Answer» i. 16xy × 18xy = 16 × 18 × xy × xy = 288x²y² ii. 23xy² × 4yz² = 23 × 4 × xy² × yz² = 92xy³z² iii. (12a + 17b) × 4c = 12a × 4c + 17b × 4c = 48ac + 68bc iv. (4x + 5y) × (9x + 7y) = 4x × (9x + 7y) + 5y × (9x + 7y) = (4x × 9x) + (4x × 7y) + (5y × 9x) + (5y × 7y) = 36x² + 28xy + 45xy + 35y² = 36x² + 73xy + 35y²

Multiply: i. 16xy × 18xy ii. 23xy2 × 4yz2 iii. (12a + 17b) × 4c iv. (4x + 5y) × (9x + 7y)

Answer»

i. 16xy × 18xy

= 16 × 18 × xy × xy

= 288x²y²

ii. 23xy² × 4yz²

= 23 × 4 × xy² × yz²

= 92xy³z²

iii. (12a + 17b) × 4c

= 12a × 4c + 17b × 4c

= 48ac + 68bc

iv. (4x + 5y) × (9x + 7y)

= 4x × (9x + 7y) + 5y × (9x + 7y)

= (4x × 9x) + (4x × 7y) + (5y × 9x) + (5y × 7y)

= 36x² + 28xy + 45xy + 35y²

= 36x² + 73xy + 35y²