Show that the equation
$$\tan \left( x - 60 ^ { \circ } \right) + \cot x = \sqrt { } 3$$
can be written in the form
$$2 \tan ^ { 2 } x + ( \sqrt { } 3 ) \tan x - 1 = 0$$
Hence solve the equation
$$\tan \left( x - 60 ^ { \circ } \right) + \cot x = \sqrt { } 3$$
for \(0 ^ { \circ } < x < 180 ^ { \circ }\).