Answer:
x = √2
Explanation:
The Pythagorean theorem tells you that for a right triangle the sum of the squares of the leg lengths is equal to the square of the hypotenuse length:
x^2 + x^2 = 2^2
2x^2 = 4 . . . . . simplify
x^2 = 2 . . . . . . divide by 2
x = √2 . . . . . . take the square root
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Please note that the hypotenuse is √2 times the leg length of every isosceles right triangle. This fact is useful in many algebra and geometry problems.