√6*cos(π-π/4)*sin(π+π/3)=√6*(-cosπ/4)*(-sinπ/3)=√6*√2/2*√3/2=1,5
6tg(180+45)*(-sin30)=-6*tg45*1/2=-3*1=-3
4tg(3π+π/3)*tg(3π-π/6)=4*tgπ/3*(-tgπ/6)=-4*√3*1/√3=-4
-2/5 х + 6 = 1/2 (х-1) домножаем на 10
X+3y=0
x^2+y^2-2xy=9
x=-3y
x^2+y^2-2xy=9
(-3y)^2+y^2-2(-3y)y=9
9y^2+y^2+6y^2=9
16y^2=9
y^2=16/9
y= 4/3 y=-4/3
x=-3*4/3 x=(-3)*(-4)/3
x=-4 x=4
Ответ: (-4;4/3), (4;-4/3)