{ y = -9/4*x +11; 80 =3x² +16(-9/4*x+11).{y = -9/4*x +11; 80 =3x² -36*x+176.
80 =3x² -36*x+176;
0 =3x² -36*x+176 -80 ;
3x² -36*x+96 =0 ;
x² -12x +32 =0;
x₁ =4 ; y₁= -9/4*x₁+11 = -9/4*4 +11 =2; (4;2).
x₂ = 8; y₂ =-9/4*x₂ +11 = -9/4*8+11 = -7 ; (8; -7).
ответ : (8; -7) , (4 ;2) первая строка .