If -3x+4y=28 and 3x-2y=8, what is the product of x and y? Answers:  A) 264 .  B) 428  C) 464 .  D) 622  E) 642

Rationale: given - 3 x + 4 y = 28 - - - eq 1 3 x - 2 y = 8 - - eq 2 sum both eqns we get 2 y = 36 = > y = 18 sub 2 y in eq 2 = > 3 x - 36 = 8 . = > x = 44 / 3 now xy = 44 / 3 * 18 = 264 . option a is correct answer .
Answer: A