+118723 cos (x/2 + 20°) = 0.39 for 0° < x ≤ 720°
$$\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{cos}}^{\!\!\mathtt{-1}}{\left({\mathtt{0.39}}\right)} = {\mathtt{67.045\: \!500\: \!598\: \!607^{\circ}}}$$
$$\\\frac{x}{2}+20 = 67^0, (360-67)^0=293^0\qquad $to the nearest degree$\\\\
\frac{x}{2}=57^0\;\;or\;\; 273^0\\\\
x=114^0\qquad or \qquad 546^0$$
+118723 cos (x/2 + 20°) = 0.39 for 0° < x ≤ 720°
$$\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{cos}}^{\!\!\mathtt{-1}}{\left({\mathtt{0.39}}\right)} = {\mathtt{67.045\: \!500\: \!598\: \!607^{\circ}}}$$
$$\\\frac{x}{2}+20 = 67^0, (360-67)^0=293^0\qquad $to the nearest degree$\\\\
\frac{x}{2}=57^0\;\;or\;\; 273^0\\\\
x=114^0\qquad or \qquad 546^0$$
