If X is the sum of first 20 positive even integers and Y is the sum of first 20 positive odd integers, what is the value of x-y?
Please try to explain your answers Choose the correct answer:
A) 0 B) 20 C) 50 D) 75 E) 100
First even minus first odd = 2-1= 
<gadget id="calculator">2-1</gadget>
<output>1</output>
1;   The sum of first 2 even integers minus the sum of first 2 odd integers= (2+4)-(1+3)= 
<gadget id="calculator">(2+4)-(1+3)</gadget>
<output>2</output>
2;   The sum of first 3 even integers minus the sum of first 3 odd integers= (2+4+6)-(1+3+5)= 
<gadget id="calculator">(2+4+6)-(1+3+5)</gadget>
<output>3</output>
3;   We can see the patterns here, so the sum of first 20 positive even integers minus the sum of first 20 positive odd integers will be 20.   Answer: 20
<result>B</result>
If X is the sum of first 20 positive even integers and Y is the sum of first 20 positive odd integers, what is the value of x-y?
Please try to explain your answers