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Problem #21 · August 17, 2026

Absolute value

On the number line, the distance from point A(−5)A(-5) to point BB is 99. Find the positive coordinate of point BB.
  1. A4
  2. B14
  3. C9
  4. D-14
  5. E-4

WORKED EXAMPLE

Solution

The distance condition is ∣b−(−5)∣=∣b+5∣=9|b - (-5)| = |b + 5| = 9. This gives b+5=9b + 5 = 9 or b+5=−9b + 5 = -9, that is, b=4b = 4 or b=−14b = -14. The question asks for a positive coordinate, so b=4b = 4.
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