{-15=-11x-12y
{4y^2=-4x^2+35x+205
y=(15-11x)/12
4(15-11x)^2/144=-4x^2+35x+205
4(225-330x+121x^2)=-576x^2+5040x+29520
900-1320x+484x^2=-576x^2+5040x+29520
1060x^2-6360x-28620=0
x^2-6x-27x=0
D=36+4*27=144
x1=(6+12)/2=9 y1=(15-11*9)/12=-7
x2=(6-12)/2=-3 y2=(15+3*11)/12=4