Question

Помогите решить номер 7.6,7.9)))

Answer 1

A) (x^2-4x)/4x=0
(x(x-4))/4x=0
(x-4)/4=0
x-4=0
x=4
б) (x^2+3x)/(5x+15)=0
(x(x+3))/(5(x+3))=0
x/5=0
x=0
в) (х^2+5х)/5х=0
(х(х+5))/5х=0
(х+5)/5=0
х+5=0
х=-5
г) (х^2-7х)/(3х-21)=0
(х(х-7))/(3(х-7))=0
х/3=0
х=0