MathDB
Symmetric Algebraic Equation

Source: 2015 amc 10a #16

February 4, 2015
VietaalgebrapolynomialsymmetryRational Root Theoremsystem of equationsAMC

Problem Statement

If y+4=(x2)2,x+4=(y2)2y+4 = (x-2)^2, x+4 = (y-2)^2, and xyx \neq y, what is the value of x2+y2x^2+y^2?
<spanclass=latexbold>(A)</span>10<spanclass=latexbold>(B)</span>15<spanclass=latexbold>(C)</span>20<spanclass=latexbold>(D)</span>25<spanclass=latexbold>(E)</span>30 <span class='latex-bold'>(A) </span>10\qquad<span class='latex-bold'>(B) </span>15\qquad<span class='latex-bold'>(C) </span>20\qquad<span class='latex-bold'>(D) </span>25\qquad<span class='latex-bold'>(E) </span>\text{30}