How do you solve -3x is less than 12?

Answer 1

You want to get x alone, as your goal, so first, you will get rid of the -3 by dividing both sides of the equation by -3. A common mistake that students make is to think it is a "minus 3," and that they would have to add 3 to get rid of it, but if it is right in front of a variable (the x), then when you are trying to solve such a problem, think of it as the x is being MULTIPLIED by a -3; therefore, you must do the opposite (divide) to get rid of it. Whatever you do to one side, you must do to the other, so we divide BOTH sides by -3. (12 divided by -3 will be -4) Inequalities (things that use the < and > symbols) have this special rule: if, when you are solving it, you have to either multiply or divide by a NEGATIVE number, the sign (< or >) has to be FLIPPED. So, we now get x > -4.