The perimeter of a rhombus is 120 cm. One of the diagonal is 36 cm. What is the length (in cm) of the other diagonal?
Show answer & explanation
Correct answer: B
Explanation
Perimeter = 4 × Side
120 = 4 × Side
Side = 30 cm
In a rhombus,
Side² = (d₁/2)² + (d₂/2)²
30² = (36/2)² + (d₂/2)²
900 = 18² + d₂²/4
900 = 324 + d₂²/4
d₂²/4 = 576
d₂² = 2304
d₂ = 48 cm