Respuesta :
a)
[tex]\boxed{x+\frac{x}{5}=12}[/tex]
b)
[tex]\boxed{x=\frac{2}{7}x+8}[/tex]
c)
[tex]\boxed{4x=12}[/tex]
d)
[tex]\boxed{x+x-7=23\rightarrow 2x-7=23}[/tex]
[tex]\boxed{x+\frac{x}{5}=12}[/tex]
b)
[tex]\boxed{x=\frac{2}{7}x+8}[/tex]
c)
[tex]\boxed{4x=12}[/tex]
d)
[tex]\boxed{x+x-7=23\rightarrow 2x-7=23}[/tex]