If x+y=5, and x=15/y, what is the value of x^2+y^2?	Options.
A) 12
B) 14
C) 16
D) 18
E) 10
x^2 + y^2 should make you think of these formulas:   (x+y)(x+y) = x^2+y^2+2xy   We already know (x+y) = 5 and x*y = 15   (x+y)(x+y) = (5)(5) = x^2+y^2+2*(15)   x^2+y^2 = 25 - 15= 
<gadget id="calculator">25 - 15</gadget>
<output>10</output>
10   Answer : 10
<result>E</result>
If x+y=5, and x=15/y, what is the value of x^2+y^2?