Answer:
x = -9
Step-by-step explanation:
The attachment shows the labeling according to the problem statement.
The overall length is the sum of the constituent segment lengths, so ...
FG + GH = FH
(10 +x) +(7) = (2x +26)
x +17 = 2x +26
x -9 = 2x
-9 = x
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Check
Then the segment length FG is ...
10 +x = 10 -9 = 1
and the overall length is ...
2x +26 = 2(-9) +26 = -18 +26 = 8
That is, 1 + 7 = 8.
