9514 1404 393
Answer:
√21
Step-by-step explanation:
The Pythagorean theorem tells you ...
a^2 +b^2 = c^2 . . . . . for legs a, b and hypotenuse c
a^2 +2^2 = 5^2 . . . . . for leg 2 and hypotenuse 5
a^2 = 25 -4 = 21 . . . . subtract 2^2
a = √21
The other leg has length √21.