1).1,5х-4х^2=6,3х-х^2
3x^2 + 4.8x = 0
x(3x + 4.8) = 0
x=0
x= -1.6
2).11у-15=(у+5)(у-3)
11y - 15 = y^2 + 2y - 15
11y - 15 - y^2 - 2y + 15 = 0
9y - y^2 = 0
y^2 - 9y = 0
y(y-9)=0
y=0
y=9
3).3х(х+2)=2х(х-2)
3x^2 + 6x = 2x^2 - 4x
x^2 + 10x = 0
x(x+10)=0
x=0
x=-10
