Solving A One-sided Inequality 2

Inequalities are similar to equations.  What is done to one side of the inequality must be compensated for on the other side.  The notable dissimilarity in arithmetic operations in inequalities is when multiplying or dividing by a negative quantity.  In such cases. the inequality sign is reversed.

Example:

Solve the inequality and show your answer using a number line.

-3y+4>16


We subtract 4 from both sides of the inequality.

-3y+4>16
      –4 –4

-3y>12

We divide by -3 and we reverse the inequality sign.

y<-4

The number line shows that y is all quantities on the number line less than and not including -4.

<---------------)--------->
                    -4