θ=.;x=3;y=3/2;a=1/2;c=Sqrt[x^2+y^2];
Manipulate[Graphics[{
Black,
Line[{{0,0},{c+1,0}}],
Line[{{0,0},{0,c+1}}],
Red,
Line[{{0,0},{0,1},{1,1},{1,0},{0,0}}],Line[{{0,0},{x,a},{x+a,y+a},{a,y},{0,0}}], 
Blue,
Line[{{0,0},{c*Cos[θ],c*Sin[θ]}}],
Line[{{-c/2*Sin[θ],c/2*Cos[θ]},{c/2*Sin[θ],-c/2*Cos[θ]}}],
Green,
Line[{{1,0},{Cos[θ]^2,Cos[θ]*Sin[θ]}}],
Line[{{0,1},{Sin[θ]*Cos[θ],Sin[θ]^2}}],
Line[{{(x+a*Tan[θ])*Cos[θ]^2,(x+a*Tan[θ])*Cos[θ]*Sin[θ]},
{x+a*Tan[θ],0}}],
Line[{{x,a},{x-a*Cot[θ],0}}],
Line[{{a,y},{0,y-a*Tan[θ]}}],
Line[{{0,y+a/Tan[θ]},{(y+a/Tan[θ])*Sin[θ]*Cos[θ],(y+a/Tan[θ])*Sin[θ]^2}}]
}],{θ,ArcTan[a/x],ArcTan[y/a]}]