Let's draw the situation to understand it better:
An isosceles triangle has two equal sides.
Let x be the length of the base
The perimeter is the add up of all sides:
Solve for x.
[tex]\begin{gathered} (5+2x)+(5+2x)+x=95 \\ 5x+10=95 \\ 5x=95-10 \\ 5x=85 \\ x=\frac{85}{5} \\ x=17 \end{gathered}[/tex]The length of the base is 17 centimeters.
