Layout Squaring (3-4-5)

Diagonal to pull and out-of-square diagnosis for a rectangular layout.

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Example

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Details, formula, and sources

Diagonal = sqrt(a^2 + b^2) (Pythagoras / the 3-4-5 rule). For a rectangle the two diagonals are equal when square, so out-of-square = |d1 - d2| and the longer diagonal's corner is the one to draw in.

The Pythagorean 3-4-5 right-angle layout method (public) and the standard foundation- and deck-squaring technique.

Public first-principles geometry; no paywalled source.

Estimate. AHJ and licensed professional govern.

Field names used by the API: mode, side_a, side_b, ideal_diagonal

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