Use some thinking to answer the following question. What is the are of an equilateral triangle of side 10 cm?
Options:
(A) 663 cm2
(B) 253 cm2
(C) 643 cm2
(D) 645 cm2
(E) 143 cm2
Area of an equilateral triangle = 3/4 S2
If S = 10, Area of triangle = 3/4 * 10 * 10 = 253 cm2; So the final answer is (B).