Big Ideas Math: Modeling Real Life, Grade 7
BI
Big Ideas Math: Modeling Real Life, Grade 7 View details
5. Solving Inequalities Using Addition or Subtraction
Continue to next subchapter

Exercise 25 Page 155

Solution: r < - 0.9
Graph:

Practice makes perfect
Inequalities can be solved in the same way as equations, by performing inverse operations on both sides until the variable is isolated. Let's use the Subtraction Property of Inequality to solve the inequality.
r + 0.2 < - 0.7
r + 0.2 - 0.2 < - 0.7 - 0.2
r < - 0.9
The above tells us that all values of r that are less than - 0.9 will satisfy the inequality. Below we demonstrate the inequality by graphing the solution set on a number line. Notice that r can not equal - 0.9, which we show with an opened circle on the number line.