tangent is opposite/adjacent, so tan(angle)=150/100
$${\mathtt{angle}} = \underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{tan}}^{\!\!\mathtt{-1}}{\left({\frac{{\mathtt{150}}}{{\mathtt{100}}}}\right)} \Rightarrow {\mathtt{angle}} = {\mathtt{56.309\: \!932\: \!474\: \!02^{\circ}}}$$
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