Subtract the second expression from the first expression:2l2 – 3lm +

1.	Subtract the second expression from the first expression:2l2 – 3lm + 5m2, 3l2 – 4lm + 6m2
Answer» Let A = 2l² – 3lm + 5m² and B = 3l² – 4lm + 6m² A – B = A + (- B) Additive inverse of B is – B = – (3t² – 4lm + 6m² ) = – 3l² + 4lm – 6m² ∴ A – B = A + (- B) = (2l² – 3lm + 5m² ) + (- 3l² + 4lm – 6m² ) = 2l² – 3lm + 5m² – 3l² + 4lm – 6m² = 2l² – 3l² – 3lm + 4lm + 5m² – 6m² = (2 – 3)l² + (- 3 + 4)lm + (5 – 6)m² = (- 1) l² + 1 lm + (- 1)m² ∴ A – B = – l² + lm – m²

Subtract the second expression from the first expression:2l2 – 3lm + 5m2, 3l2 – 4lm + 6m2

Answer»

Let A = 2l² – 3lm + 5m² and

B = 3l² – 4lm + 6m²

A – B = A + (- B)

Additive inverse of B is

– B = – (3t² – 4lm + 6m² )

= – 3l² + 4lm – 6m²

∴ A – B = A + (- B)

= (2l² – 3lm + 5m² ) + (- 3l² + 4lm – 6m² )

= 2l² – 3lm + 5m² – 3l² + 4lm – 6m²

= 2l² – 3l² – 3lm + 4lm + 5m² – 6m²

= (2 – 3)l² + (- 3 + 4)lm + (5 – 6)m²

= (- 1) l² + 1 lm + (- 1)m²

∴ A – B = – l² + lm – m²