Answer :
3500-80x=250+10x
3500=250+90x
3250=90x
3250/90
X=36.1 repeating
3500=250+90x
3250=90x
3250/90
X=36.1 repeating
[tex]3500-80x=250+10x\\
-90x=-3250\\
x=\frac{325}{9}\approx36.1[/tex]