Exercise 16 Page 396

Inequalities can be solved in the same way as equations, by performing inverse operations on both sides until the variable is isolated. The only difference is that when we divide or multiply by a negative number, we must reverse the inequality sign.

y-21 < 85

AddIneq

LHS+21

y-21+ 21 < 85+ 21

AddTerms

Add terms

y < 106

Note that all values of y less than 106 satisfy the inequality. Now let’s graph the inequality on a number line. Since y cannot equal 106, we draw an open circle at this point. Since y is less than 106, we will shade the part of the number line that represents numbers less than 106. This means that we shade to the left of our point at 106.