Question

if sides of equilateral triangle are tripled find its area

Answer 1

Area of an equilateral triangle A = √3 a²/4  where a is the side

If the side is tripled, then A = √3 (3a)² /4 = 9 √3/4 a²

The area becomes 9 times or 900 % : increase in AREA is 800%
The side becomes 3 times or 300%  : increase in side is 200%

Answer 2

Area of equilateral triangle = √3/4a²

the sides are tripled i.e 3a

Area of the triangle when side is tripled = √3/4 ×( 3a)² = √3/4 × 9a²