Answer:
A
Step-by-step explanation:
We know that , the angle sum property of a triangle is 180°. That is the sum of all angles in a triangle is equal to 180 degree .
On adding all the angles :-
[tex]:\implies[/tex] 3x+14°+45°+85° = 180°
[tex]:\implies[/tex] 3x + 144° = 180°
[tex]:\implies[/tex] 3x = 180° - 144°
[tex]:\implies[/tex] 3x = 36°
[tex]:\implies[/tex] x = 36°/3
[tex]:\implies[/tex] x = 12°
Hence the value of x is 12° ( Option A) .
