From Förberedande kurs i matematik 1

By taking \displaystyle 4y out of the relation \displaystyle 3x+4y-5=0, we get

\displaystyle 4y=-3x+5\,\textrm{.}

Dividing by 4 then gives the answer in the desired form

\displaystyle y=-\frac{3}{4}x+\frac{5}{4}\,\textrm{.}