From a formula located here:
http://www.1728.org/quadltrl.htm
we see that
<span>4 • Side² = Long Diagonal² + Short Diagonal²
Long Diagonal = 24
Short Diagonal = 10
</span><span>4 • Side² = 24^2 + 10^2 </span>
<span>4 • Side² = 576 + 100
</span><span>4 • Side² = 676
</span><span><span>Side²</span> = 169
Side (or line AB) = 13
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