tanx= -1.5

$$\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{tan}}^{\!\!\mathtt{-1}}{\left(-{\mathtt{1.5}}\right)}{\mathtt{\,\times\,}}\left({\frac{{\mathtt{\pi}}}{{\mathtt{180}}}}\right) = -{\mathtt{0.982\: \!793\: \!723\: \!247\: \!325\: \!3}}$$