What is the side of a right angle triangle where the known angle is 36 deg and the known side is 12

tan(angle) = opposite/adjacent, so opposite = adjacent*tan(angle)

$${\mathtt{opposite}} = {\mathtt{12}}{\mathtt{\,\times\,}}\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{tan}}{\left({\mathtt{36}}^\circ\right)} \Rightarrow {\mathtt{opposite}} = {\mathtt{8.718\: \!510\: \!336\: \!06}}$$

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