Answer:
[tex]m\angle MNI = 135^{\circ}[/tex]
Step by step explanation:
[tex]\text{The exterior angle of a triangle = sum of two opposite interior angles.}[/tex]
[tex]~~~~~~\angle MNI = \angle LMN + \angle MLN\\\\\implies 19x+2=(15x-12)+6x\\\\\implies 19x +2 = 21x-12\\\\\implies 21x -19x = 12+2\\\\\implies 2x = 14\\\\\implies x=\dfrac {14}2\\\\\implies x = 7\\\\\text{So,}~ m\angle MNI = 19(7)+2=135^{\circ}[/tex]
