Question

(2.5y-4)(6y-1.8)=0

Answer 1

15y^2-4,5y-24y+7.2=0

15y^2-28,5y+7,2=0

D=812,25-432=380,25=19.5^2

x1=(4,5+19,5)30=0,8

x2=(4,5-19,5)30=-0,5