Wie wird der Satz des Pythagoras gerechnet?

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$${{\mathtt{c}}}^{{\mathtt{2}}} = {{\mathtt{a}}}^{{\mathtt{2}}}{\mathtt{\,\small\textbf+\,}}{{\mathtt{b}}}^{{\mathtt{2}}}$$

$${{\mathtt{a}}}^{{\mathtt{2}}} = {{\mathtt{c}}}^{{\mathtt{2}}}{\mathtt{\,-\,}}{{\mathtt{b}}}^{{\mathtt{2}}}$$

$${{\mathtt{b}}}^{{\mathtt{2}}} = {{\mathtt{c}}}^{{\mathtt{2}}}{\mathtt{\,-\,}}{{\mathtt{a}}}^{{\mathtt{2}}}$$

Beispiel: a=3 cm, b=4 cm

 $${{\mathtt{c}}}^{{\mathtt{2}}} = {{\mathtt{3}}}^{{\mathtt{2}}}{\mathtt{\,\small\textbf+\,}}{{\mathtt{4}}}^{{\mathtt{2}}}$$

$${{\mathtt{c}}}^{{\mathtt{2}}} = {\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{16}}$$

$${{\mathtt{c}}}^{{\mathtt{2}}} = {\mathtt{25}}$$

$${\mathtt{c}} = {\mathtt{5}}$$