x^2+y^2+3xy-1=0
по дискриминанту
((1/5)^2)^(-3/2) * ((1/2)^3)^(-4/3) - ((1/11)^2)^(-1/2) = (1/5)^(-3) * (1/2)^(-4)- (1/11)^(-1)=
=(5^3) * (2^4) - 11 = 125*16 - 11 = 1989