Question 6 • Mathematics III A
First expand the product: (x – 4)(x + 5) = x² + 5x – 4x – 20 = x² + x – 20. Then combine the remaining like terms: 7x + x – 5x = 3x. The simplified expression is x² + 3x – 20, which is choice B.
AI-written and checked against the verified answer.