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Again, @CubeyThePenguin "solves" the problems even without reading their descriptions.
I must go to fix after him / (her)
= 224
20 + x = = 28
x = 28 - 20 = 8.
ANSWER. the length of the other base is 8 meters.
Solved.
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For your safety, ignore the post by @CubeyThePenguin, since it is T O T A L L Y W R O N G.