Basic Math Examples

21

$21$

Step 1

The factors for

21

$21$ are all numbers between

- 21

$- 21$ and

21

$21$ , which divide

21

$21$ evenly.

Check numbers between

- 21

$- 21$ and

21

$21$

Step 2

Find the factor pairs of

21

$21$ where

x \cdot y = 21

$x \cdot y = 21$ .

\begin{matrix} x & y 1 & 21 3 & 7 - 1 & - 21 - 3 & - 7 \end{matrix}

$\begin{array}{c} x & y \\ 1 & 21 \\ 3 & 7 \\ - 1 & - 21 \\ - 3 & - 7 \end{array}$

Step 3

List the factors for

21

$21$ .

- 21, - 7, - 3, - 1, 1, 3, 7, 21

$- 21, - 7, - 3, - 1, 1, 3, 7, 21$