Answer :
[tex] \frac{\big{3+y}}{\big{y}}=7\ \ \ \Rightarrow\ \ \ D:\ y \neq 0\\\\ \frac{\big{3+y}}{\big{y}}\cdot y=7\cdot y\\\\3+y=7y\\\\y-7y=-3\\\\-6y=-3\ /:(-6)\\\\y= \frac{3}{6} \\\\y= \frac{1}{2} \ \in\ D[/tex]
[tex] \frac{3 + y}{y} = 7 \\ \\ 3 +y = 7y \\ \\ 1y - 7y = -3 \\ \\ -6y = -3 \\ \\ y = \frac{-3}{-6} = \frac{1}{2} \\ \\ y = \frac{1}{2} [/tex]
