Answers

2016-01-05T22:45:10+08:00
The three angles are 3x, 4x and 5x
The sum of the three angles of a triangle is always 180. So,
3x + 4x + 5x = 180
12x = 180
x = 15
So the three angles are 45, 60, and 75. 
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2016-01-06T18:48:54+08:00
You have here...

3x+4x+5x= 180 (which is the sum of the angles in a triangle)
12x= 180
x= 15

you got x, so here...

3(15)= 45
4(15)= 60
5(15)= 75
proof???

45+60+75=180
180=180
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