Solve |2x - 5| = 7.

• A. x = 6
• B. x = -1
• C. x = 6 or -1
• D. x = 5

Answer: (C)

When absolute value equals a number, you consider both the positive and negative inside the absolute value.

|2x - 5| = 7 leads to two equations: 2x - 5 = 7 and 2x - 5 = -7.

From the first, x = 6. From the second, x = -1.

So x can be 6 or -1. Check: |2(6) - 5| = |12 - 5| = 7 and |2(-1) - 5| = |-2 - 5| = 7, so both work. The value that lists both 6 and -1 is the correct one.