# How do you multiply (x + 3)(x + 4)?

Apr 29, 2018

Use the distributive property.

#### Explanation:

One way is to set this up as a square matrix

$$     x       +      3


x $\left(x \times x\right) + \left(3 \times x\right)$

+

4 $\left(4 \times x\right) + \left(3 \times 4\right)$

This gives ${x}^{2} + 3 x + 4 x + 12$ Adding the like terms gives

${x}^{2} + 7 x + 12$