Question

find ( mangle mqn ).
first, find ( mangle jqk ).
( mangle jqk=) ? ( ^{circ} )

Explanation:

Step1: Use vertical angles property

Vertical angles are equal. $\angle JQK$ and the angle of $30^{\circ}$ are vertical angles.

Step2: Calculate $m\angle JQK$

Since vertical angles are equal, $m\angle JQK = 30^{\circ}$

Answer:

$30$