2023 · Q57
A triangle has sides 13 cm, 14 cm and 15 cm long. What is the length of the smallest altitude of the triangle?
Elementary MathematicsMensuration
- A11 cm
- B11.2 cm
- C12 cm
- D12.2 cm
Explanation
For sides 13, 14, 15 the semiperimeter is s = 21 and the area is √(21·8·7·6) = √7056 = 84 cm². The smallest altitude corresponds to the longest side (15 cm): h = 2·Area/base = 168/15 = 11.2 cm. The answer is (B).