1,5x(x+4)-x(7-0,5x)=0,5(10-2x)
1.5x^2+6x-7x+x^2*0.5-0.5*(10-2x)=0
2x^2-x-(5-x)=0
2x^2-x-5+x=0
2x^2-5=0
D=0^2-4*2*(-5)=-(-8*5)=40
x1=V40/4 (~1.58)
x2=-V40/4 (~-1.58)
V - квадратный корень
A = bc/2 - bd/2
bd/2 = bc/2 - a
bd = bc - 2a
d = (bc - 2a)/b
2x+3y=-12/ *(-2)
4x-6y=0
-4x-6y=24
4x-6y=0
-12y=24/ /(-12)
y=-2
x=-3