The diagram below shows a diagram of a new bridge. An engineer took some measurements and found that a=1135, b=805 and c=1340.
How long is the bridge?
 ft
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Use pythagorean’s theorem and find the missing side lengths of the two smaller triangles and add them together
13^2 - 12^2 = 5
15^2 - 12^2 = 9
5+9 = 14
14 is the length of each side of the square
14^2 + 14^2 = 19.8
19.8 is the diagonal length of the inside if the square