The area of a regular triangle increases by 44%. By what percentage did the side length increase?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 20%.
Area of equilateral triangle ∝ (Side)2
Let old area = A, New area = 1.44A
(New side/Old side)2 = 1.44A/A = 1.44
New side/old side = √1.44 = 1.2
Increase = 0.2
Increase percentage = 0.2 × 100 = 20%