Since congruence and similarity for polygons is posted in a specific order, we know that angle A=angle F, side A=side F, die B=side G, and so on. Therefore, we have that angle C=angle H = 9x-7=5x+13. Subtracting 5x from both sides to separate the x using the subtraction property of equality, we get 4x-7=13. Next, we can add 7 to both sides to get 4x=20, and divide both sides by 4 to isolate the x and get x=5. Plugging that into angle C or angle H, we get that 9x-7=9*5-7=45-7=38=5*5+13.
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