In regular polygon, exterior angle + interior angle = 180o
Therefore 180 - $\frac{360^o}{n}$ = 150o
180o - 150o = $\frac{360^o}{n}$; 30o = $\frac{360^o}{n}$
30n = 360 n = 12
n -2 triangles; 12 - 2 = 10
johnmulu answered the question on March 6, 2017 at 09:26
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