First, we need to know the equation of the line
[tex]y=mx+b[/tex]
m is the slope
b is the value of y-intercept
in the first equation
[tex]-2x+y=3[/tex]
we need to clear y in order to have the same form of the equation of the line
[tex]y=2x+3[/tex]
m=2
b=3
in the second equation, we do exactly the same
[tex]\begin{gathered} -x+4y=12 \\ 4y=x+12 \\ y=\frac{1}{4}x+\frac{12}{4} \\ y=\frac{1}{4}x+3 \end{gathered}[/tex]
m=1/4
b=3
