Hello @Skykeeper42! Welcome to this forum!
Multiplying the second equation by $2$, we get $4y=f(2x)+4$. So, because $(9,7)$ is on the graph of f(x), $x=\frac{9}{2}$ must be on the x graph of $4y=f(2x)+4$.
Now, just plug it in, and we get $f(2\frac{9}{2})=f(9)=7$, so $4y=7+2$, or $4y=9$, so $y=\frac{9}{4}$.
Now, summing up $\frac{9}{2}+\frac{9}{4}=\boxed{\frac{27}{4}}$
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