If the sum and difference of two numbers are 10 and 19 respectively, then the difference of their square is:
Choose the correct option
A) 12 B) 28 C) 160 D) 180 E) 190

Rationale: let the numbers be x and y . then , x + y = 10 and x - y = 19 x 2 - y 2 = ( x + y ) ( x - y ) = 10 * 19 = 190 . answer : e
Answer: E