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Question from jarred, a student:

3x+8>2

Jarred,

You can solve inequalities very much as you solve equalities, but there is one difference. If you multiply or divide both sides of an inequality by a negative number you must reverse the direction of the inequality. Let me illustrate with

Solve 5 - 4x < 13

The first step is to add -5 to each side to get

5 - 4x - 5 < 13 - 5

or

-4x < 8

Next multiply both sides by -1/4. Since -1/4 is negative I must reverse the direction of the inequality to get

(-4x) × (-1/4) > 8 × (-1/4)

which simplifies to

x > -2

Now try your problem,
Penny

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