Question

Помогите,пжл. 3х+28=20х

Answer 1

3х+28=20/х |•х
3х^2+28х=20
3х^2+28х-20=0
D=28^2-4×3×(-20)=784+240=1024
х1=-28+32/2×3=4/6=2/3
х2=-28-32/2×3=-60/6=-10