If the sum and difference of two numbers are 20 and 10 respectively, then the difference of their square is:  Choose the correct choice from the following choices:	A) 12	B) 28	C) 160	D) 200	E) 18
Let the numbers be x and y.   Then, x + y = 20 and x - y = 8   x2 - y2 = (x + y)(x - y) = 20 * 10= 
<gadget id="calculator">20 * 10</gadget>
<output>200</output>
200.   ANSWER:200
<result>D</result>
If the sum and difference of two numbers are 20 and 10 respectively, then the difference of their square is: