Hello!
First you have to find angle BDA
The angles in a triangle add to 180
Subtract the know angles to get the missing one
180 - 60 - 75 = 45
Angle BDA = 45
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Next you find what angle ACD measures
The angles in a triangle add to 180
Subtract the know angles to get the missing angle
25 + 45 = 70
180 - 70 - 60 = 50
Angle ACD is 50
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Now you can find angle CBD
The angles in a triangle add up to 180
Subtract the know angles to get the unknown one
180 - 25 - 50 = 105
Angle CBD is 105
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Since Triangle DBC has one obtuse angle it is an obtuse triangle
The answer is A) obtuse triangle
Hope this helps!