Given the function:
[tex]\begin{gathered} f(x)=2x-5\rightarrow(1) \\ \\ f(x)=15\rightarrow(2) \end{gathered}[/tex]
We will substitute with the value of f(x) from equation (1) into equation (2), then solve for x as follows:
[tex]\begin{gathered} 15=2x-5 \\ 15+5=2x \\ 20=2x \\ \frac{20}{2}=x \\ \\ x=10 \end{gathered}[/tex]
So, the answer will be x = 10
