# How do you solve #3x + 6 = 21#?

##### 1 Answer

Feb 29, 2016

#### Explanation:

Following the correct rules in math:

Subtract both sides with "-6" to isolate 3x, making the equation looks like this:

Divide both sides by 3 to come up with x, making the equation:

Final answer is:

SHORTCUT METHOD:

This one does not follow the correct rules in math but this is very helpful for "limited time" exams.

Transfer +6 to other side of the equation, converting the sign to opposite one making +6 to -6

Subtract

Divide it by the number with

Final answer