Answers

2015-09-22T17:52:46+05:30
Sum of angles of a triangle is 180°. therefore, x-40+x-20+1/2x-10=180. i.e. 2x+x/2-70=180. 2x+x/2=250. 5x=500 x=100°
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2015-09-22T18:00:16+05:30
(x-40)+(x-20)+(1/2x-10)=180° [ angle sum property of a triangle]
x-40+x-20+1/2x-10=180°
2x+1/2x-70=180°
5/2x=180°+70
5/2x=250°
x=250°*2/5
therefore, x=100

And the values of the angles are:
100-40=60
100-20=80
1/2*100-10=40
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