Question

When solving an inequality, when do you reverse the inequality sign?

A) never
B) always
C) when there is a negative in the answer
D) when you multiply or divide both sides by a negative

Answer 1

The answer is D. To see why, forget about equations with variables and just look at some numbers:

3 < 5

That's obviously correct, right? Now multiply both sides by -2:

3 * -2 < 5 * -2
-6 < -10

That's not right, and you need to flip the < to > to make it right:

-6 > -10

The same thing applies to division.

Answer 2

d. whenever you multiply or divide both sides by a negative