KMO 2015 Problem 3

Reals $a,b,c,x,y$ satisfies $a^2+b^2+c^2+x^2+y^2=1$ . Find the maximum value of $(ax+by)^2+(bx+cy)^2$

Dataset text AI-MO AoPS. Quoted with source.

Solutions

No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.