Let the number of saxophone players be [tex]s[/tex].
Then, the number of trumpet players will be [tex]s-10[/tex]
If saxophone players are three times the number of trumpet players then we have the relation
[tex]s=3(s-10)[/tex]
This is a linear equation in s. we expand bracket to obtain,
[tex]s=3s-30[/tex]
We group like terms to get,
[tex]s-3s=-30[/tex]
[tex]-2s=-30[/tex]
This implies that
[tex]s=15[/tex]
The number of trumpet players are;
[tex]15-10=5[/tex]
Therefore there are 5 trumpet players.