Answer:

Step-by-step explanation:
✰ 
The angles which are formed inside by the joining of arms of a triangle is called interior angles of a triangle. According to the figure provided , In ∆ ABC , ∠ABC , ∠ ACB , ∠ BAC are interior angles because they lie inside the ∆ ABC and sum of such interior angles is always 180°.
❀ 
☄ 
- ∠B = 3x°
- ∠ C = 4x°
- ∠ A = 2x°
☄ 
✏ 

→ 
→ 
→ 
→ 
The value of x is 20°. As we are asked to find the measure of ∠C , substituting the value of x in 4x :

→ 
→ 
Hence , The measure of ∠ C is 80 °
Hope I helped ! ッ
Have a wonderful day / night ! ♡
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