How does quadrea relate to area?

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In NJ Wildeberger's book (which I don't see much use in citing, since its an offline material, so instead I will provide a link to his key points further down) he argues that "Quadrance" can be just as useful as "Distance". He defines Quadrance as: "A squared plus B squared" & "(((C - A)^2)+((B - D)^2)) given lines 'AB' and 'CD'. More info here: " https://www.quora.com/Is-N-J-Wildberger-a-joke-or-a-genius-when-he-claims-that-mathematics-in-its-current-form-is-a-hoax " & here: " https://en.m.wikipedia.org/wiki/Rational_trigonometry " . Now knowing quadrance fills the shoes of distance; what fills the shoes of area? And how can it be converted back into its 'non-rational' equivalent?

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The definition of quadrea is $ (Q_1+Q_2+Q_3)^2-2(Q_1^2+Q_2^2+Q_3^2).\;$ If $\;d_21^2=Q_1,\;$ $d_2^2=Q_2,$ $d_3^2=Q_3$, then it is $(d_1+d_2+d_3)(-d_1+d_2+d_3)(d_1-d_2+d_3)(d_1+d_2-d_3)$ and by Heron's formula this is $16$ times the square of the area of the triangle.

This can be checked by looking at an equilateral triangle side $d$ whose area squared is $\frac3{16}d^4.$