Решите уравнение 1) (1,8-0,3у)(2у+9)=0 2)(5у+4)(1,1у-3,3)=0

1) (1.8-0.3y)(2y+9)=0
3.6y+16.2-0.6y²-2.7y=0
-0.6y²+0.9y+16.2=0
-6y²+9y+162=0
-2y²+3y+54=0
D=9-4*(-2)*54=441
x1=(-3+21)/(-4)=-4.5
x2=(-3-21)/(-4)=6

2) (5y+4)(1.1y-3.3)=0
5.5y²-16.5y+4.4y-13.2=0
5.5y²-12.1y-13.2=0
55y²-121y-132=0
5y²-11y-12=0
D=121-4*5*(-12)=361
x1=(11+19)/10=3
x2=(11-19)/10=-8/10=-4/5=-0.8