Answer:
15.56 inches
Step-by-step explanation:
Let L represent the leg length. Then the Pythagorean theorem tells you ...
... 22² = L² + L² . . . . the square of the hypotenuse is the sum of the squares of the other two sides
... 484 = 2L² . . . . . . . simplify
... 242 = L² . . . . . . . . divide by 2; next, take the square root
... √242 = L ≈ 15.56 . . . . inches
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Comment on this problem in general
For a hypotenuse of length H, the above equation becomes ...
... H² = L² +L² = 2L²
... H²/2 = L² . . . . . divide by 2
... H/√2 = L . . . . . take the square root (general solution for isosceles right triangles)
For your problem, this is ...
... (22 in)/1.414214 = L = 15.556 in