I got the same answer as Chris,
\(7=f(9)\\ 7=f(2*4.5)\\ \text{So if }x=4.5, f(2x)=7\\\)
\(2y=\frac{f(2x)}{2}+2\\ When \;\;x=4.5\\ 2y=\frac{7}{2}+2\\ y=\frac{7}{4}+1\\ y=1\frac{3}{4}+1\\ y=2\frac{3}{4}\\ \text{So one point on the graph is }(4\frac{1}{2},2\frac{3}{4})\\~\\ \text{The sum of the coordinates is } 7\frac{1}{4} \)
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