Question

Multiply out 5x(2x-3y)

Answer 1

Expand

5x × 2x + 5x × -3y

Rake out the constants

(5 × 2)x + 5x × -3y

Simplify 5 × 2 to 10

10x + 5x × -3y

Use the product rule: x^ax^b = x^a + b

10x^2 + 5x × -3y

Simplify 5x × -3y to -15xy

= 10x^2 - 15xy

Answer 2

You start by distributing the 5x, so that it’s 5x(2x) and 5x(3y). That becomes 10x^2 and 15xy. Put it back, and it’s 10x^2 - 15xy.