Double Distributive Property -- Visual Examples, Practice Problems and pictures

Like Foil, the double distributive method is used for multiplying 2 binomials.

How "double" distributive works:

Unlike "single" distribution which only distributes 1 single term, double distribution requires two terms (a binomial) to distribute over a second binomial.

So, in this example, you have to distribute that first x and also that 5 over the second binomial.

Use double distributive method to simplify $$ (x - 3)(x + 7) $$.

Step 1

Distribute out both terms.

Step 2

Simplify like terms.

$ -3x -21 + x^2 + 7x \\ x^2 + 4x - 21 $

Use double distributive method to simplify $$ (x - 3)(x + 3) $$.

Step 1

Distribute out both terms.

Step 2

Simplify like terms.

$ -3x -9 + x^2 + 3x \\ x^2 \red{-3x + 3x} -9 \\ x^2 -9 $

Use double distributive method to simplify $$ (x - 2)(2x + 6) $$.

Step 1

Distribute out both terms.

Step 2

Simplify like terms.

$ -4x -12 + 2x^2 + 6x \\ 2x^2 +2x - 12 $

Use double distributive method to simplify $$ (x - 8)(3x - 1) $$.

Step 1

Distribute out both terms.

Step 2

Simplify like terms.

$ -24x +8 + 3x^2 -x \\ x^2 -25x +8 $

Double Distributive Method for Multiplying Binomials