If the sides of a right triangle have lengths x - 3, x + 1, and x + 5, then x = _____?
- 12
- 15
- 18
- None of these
Explanation
(x-3)² + (x+1)² = (x+5)²
x² - 6x + 9 + x² + 2x + 1 = x² + 10x + 25
2x² - 4x + 10 = x² + 10x + 25
x² - 14x - 15 = 0
(x-15)(x+1) = 0
x = 15 or x = -1
x = 15 fits the given lengths are positive.
Last verified on 09-03-2026