Question

How do you solve and graph `-3n > 9`?

Answer 1

`n < -3`

Explanation:

`-3n > 9`

To solve for `n`, divide both sides by `color(blue)(-3)`. However, when we multiply or divide by a negative value in inequalities, the sign changes. In this example, the `>` would change to `<`:
`(-3n)/color(blue)(-3) color(blue)(<) 9/color(blue)(-3)`

Therefore,
`n < -3`

Here's a graph of it on a number line:

(mathwarehouse.com)

The open circle on the `-3` means that it is no a solution (but anything less than it is).

Hope this helps!