The standard form:
[tex]Ax+By=C[/tex]
[tex]4x-y-7=0\qquad\text{add 7 to both sides}\\\\\boxed{4x-y=7}[/tex]
[tex]3x+9=\dfrac{7}{2}y\qquad\text{multiply both sides by 2}\\\\6x+18=7y\qquad\text{subtract 18 and 7y from both sides}\\\\\boxed{6x-7y=-18}[/tex]
[tex]y=-4x+12\qquad\text{add 4x to both sides}\\\\\boxed{4x+y=12}[/tex]
[tex]y=-\dfrac{3}{4}x+\dfrac{5}{4}\qquad\text{multiply both sides by 4}\\\\4y=-3x+5\qquad\text{add 3x to both sides}\\\\\boxed{3x+4y=5}[/tex]
