In rhombus abcd, the diagonal line ac and line bd intersect at e. if ae=5 and be = 12, what is the length of line ab?

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

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