Find the area of a rhombus whose side is 25 cm and one of the diagonals is 30 cm?  Choose the correct choice from the following choices
A) 600
B) 881
C) 767
D) 261
E) 121

Rationale: consider the rhombus abcd . let the diagonals intersect at e . since diagonals bisect at right angles in a rhombus . be 2 + ae 2 = ab 2 252 = 152 + ae 2 ae = √ ( 625 - 225 ) = √ 400 = 20 , ac = 20 + 20 = 40 cm . area of a rhombus = 1 / 2 * d 1 d 2 = 1 / 2 * 40 * 30 = 600 sq . cm . answer : a
Answer: A