If x + y = 2 and x^2 - xy - 10 - 2y^2 = 0, what does x − 2y equal?	Select the correct option
A) 0  B) 1  C) 2  D) 5  E) 10
If x + y = 2 and x^2 - xy - 10 - 2y^2 = 0, what does x − 2y equal?   A. 0   B. 1   C. 2   D. 5   E. 10   Since x + y = 2 we have y=2-x.   So 0= x^2 - xy - 10 - 2y^2 = x^2 - x(2-x) - 10 - 2(2-x)^2 = x^2 -2x+x^2 -10-8+8x-2x^2 = x=6x-18. ---&gt; x=3 ---&gt; y= -1 ---&gt;x-2y=5   The answer is (5).
<result>D</result>
If x + y = 2 and x^2 - xy - 10 - 2y^2 = 0, what does x − 2y equal?