The Distributive Law

Expanding and factoring

An interactive lesson with 7 steps, about 6 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Distributive law: a(b + c) = ab + ac; the outside factor multiplies every term.
• Watch the signs: −2 × −5 = +10.
• Factoring reverses expanding: take out the highest common factor.

Steps

1. One rectangle, two parts
2. Mental arithmetic
3. Expand it
4. A negative outside
5. Factoring: running it backwards
6. Take out the factor
7. Factor to calculate