If the sum and difference of two numbers are 10 and 19 respectively, then the difference of their square is: Choose the correct answer:
A) 12
B) 28
C) 160
D) 180
E) 190
Let the numbers be x and y.   Then, x + y = 10 and x - y = 19   x2 - y2 = (x + y)(x - y) = 10 * 19= 
<gadget id="calculator">10 * 19</gadget>
<output>190</output>
190.   ANSW190R:190
<result>E</result>
If the sum and difference of two numbers are 10 and 19 respectively, then the difference of their square is: