Answer:
AB=sqrt(53)
Explanation:
consider the right angle triangle of the top rectangle w sides of 6 n 4
diagonal^2 = 6^2 + 4^2
consider the right angle triangle of the diagonal, AB and 1
AB^2 = diagonal^2 + 1^2
= 6^2 + 4^2 + 1^2
= 36 + 16 + 1
=53
AB=sqrt(53)
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