If x+y=4 and x2y3 + y2x3=36, what is the value of xy?  Answers.
A) 1 B) 2 C) 3 D) 4 E) 5
xy=3   As x+y=4   x2y3+y2x3=36   x2y2(y+x)=36   Substituting x+y   x2y2=4   xy=4   ANSWER:4
<result>D</result>
If x+y=4 and x2y3 + y2x3=36, what is the value of xy?