Question 1062917
.
<pre>
The sum of interior angles of a triangle is 180 degs.

Therefore,

(x-12) + (x-8) + (4x+20) = 180,

6x = 180  ---->  x = {{{180/6}}} = 30   ---->  

< A = x - 12 = 30 - 12 = 18 degs,

< B = x - 8 = 30 - 8 = 22 degs, 

< C = 4x + 20 = 4*30 + 20 = 140 degs.
</pre>

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