A triangle has sides in the ratio 3:4:5 and a perimeter of 36 cm. Find its area.
Show answer & explanation
Correct answer: A
Explanation
Let the sides be 3x, 4x, and 5x.
Perimeter = 3x + 4x + 5x = 12x
12x = 36
x = 3
The sides are 9 cm, 12 cm, and 15 cm.
Area = (1/2) × Base × Height
Area = (1/2) × 9 × 12 = 54 cm²