Answer:
[tex]A=\frac{15}{x} -\frac{3y}{x}[/tex]
Step-by-step explanation:
Question: [tex]ax+3y=15[/tex]
1) Subtract 3y from both sides:
[tex]ax=15-3y[/tex]
2) Divide both sides by x:
[tex]a=15/x-3y/x[/tex]