Question

1. Giles thinks that -5x²(3x - 4) simplifies to 15x² + 20x². Explain what mistakes he made. What is the

correct answer?

Answer 1

The mistake was minus sign before the 15 and putting 15x² instead of 15x³.

The correct answer is:

`-5x^(2) (3x-4)\\ = -15x^(3) + 20x^(2)`