# Calculate the angles in the triangle

#### Dafoe

Need some help with this one. Please be detailed and methodic in your understandable explanations because I find this very difficult.

http://a.imagehost.org/0288/n_5.jpg [Broken]

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#### luke young

basically all the angles in a triangle have to add up to 180' degrees, depending on the triangle formation you can tell what one of the angles could be - i.e a right angle triange will have a 90' degree angle and a icosilees (cant spell) triangle will have two angles the same and one different, an equilateral triangle all angles the same.

#### LCKurtz

Homework Helper
Gold Member
I will give you a couple of hints to get you going. Call the center of the circle O and draw lines from O to A, B, and C. These lines will make three isosceles triangles with the sides of the given triangle. The theorem from geometry you need to remember is that the central angle is twice the size of an inscribed angle subtended by the same arc. For example, in this problem, angle AOC is twice angle you have labeled 80 degrees. So you should be able to figure out the central angles in that triangle and use the isosceles triangles to get the others. Good luck.

#### Dafoe

I will give you a couple of hints to get you going. Call the center of the circle O and draw lines from O to A, B, and C. These lines will make three isosceles triangles with the sides of the given triangle. The theorem from geometry you need to remember is that the central angle is twice the size of an inscribed angle subtended by the same arc. For example, in this problem, angle AOC is twice angle you have labeled 80 degrees. So you should be able to figure out the central angles in that triangle and use the isosceles triangles to get the others. Good luck.
Ok thanks. But there must be a easier way to look at the problem