9514 1404 393
Answer:
10
Explanation:
The Pythagorean theorem tells you ...
b² + 24² = 26²
b² = 26² -24² = 676 -576 = 100
b = √100 = 10
The length b of the other side is 10.
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You may recognize this as a 5-12-13 right triangle, scaled by a factor of 2.