(9х-3)*(5х+2)*(х²+4х)=0; (9х-3)=0; х=3/9=1/3; (5х+2)=0; х=-2/5; (х²+4х)=0; х*(х+4)=0; х=0; х=-4.
8. (4х-1)*(5х+7)-(1-4х)+(4х-1)*(3х+2)=0; (4х-1)*(5х+7+1+3х+2)=0; 4х=1;х=1/4=0.25; (8х+10)=0;х=10/8=5/4=1.25
9.(5у²+у)*(3у-1)+2(у+5у²)=0; (у+5у²)*(3у-1+2)=0;
у+5у²=0;у*(1+5у)=0; у=0; у=-1/5
(3у-1+2)=0; 3у+1=0; у=-1/3.