Chapter 3 - Solving Inequalities - 3-7 Absolute Value Equations and Inequalities - Practice and Problem-Solving Exercises - Page 211: 25

f=−2 or f=1.5

|4f+1|−2=5⟶ add 2 to each side |4f+1|−2+2=5+2⟶ add |4f+1|=7⟶ definition of absolute value 4f+1=−7 or 4f+1=7⟶ solve each equation 4f+1=−7⟶ subtract 1 from each side 4f+1−1=−7−1⟶ subtract 4f=−8⟶ divide each side by 4 4f÷4=−8÷4⟶ divide f=−2 OR 4f+1=7⟶ subtract 1 from each side 4f+1−1=7−1⟶ subtract 4f=6⟶ divide each side by 4 4f÷4=6÷4⟶ divide f=1.5