Answer :
Let the first angle be x
So, second angle = (x+15)°
and third angle= (x+ 45)°
Now,
x+ (x+15) + (x+45)= 180°. ( Triangle sum property)
x+x+x+15°+45° = 180°
3x+ 60° = 180°
3x= 180°-60°
3x= 120°
x= 120°/3
x= 40°
Now,
first angle=x= 40°
second angle = (x+15)°= 40°+15° = 55°
third angle= (x+45)° = 40°+45° = 85°
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