Question 1126331
Try to isolate any terms of y on one side.


{{{y/b=1-x/a}}}



Multiply both sides by  b.


{{{b(y/b)=b(1-x/a)}}}


{{{y=b-bx/a}}}   and you can use fraction arithmetic to make the right side as one single expression, if you want it that way, which you did already, correctly.