9514 1404 393
Answer:
14.14
Explanation:
The diagonal of a square is √2 times the side length.
AC = AB×√2
AC = 10√2 ≈ 14.14
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The diagonal of a square is the hypotenuse of an isosceles right triangle. If the sides of that are s and the diagonal is d, the Pythagorean theorem tells us ...
d² = s² + s²
d² = 2s²
d = (√2)(√s²) = s√2
This relation holds for any isosceles right triangle, not just for the diagonal of this square. It is useful to remember.