Calculate the angles in the triangle

In summary, to solve this problem you need to figure out the central angles and use the isosceles triangles to find the other angles.
  • #1
Dafoe
7
0
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
 
Last edited by a moderator:
Physics news on Phys.org
  • #2
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.
 
  • #3
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.
 
  • #4
LCKurtz said:
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
 
  • #5
I don't think so. This is pretty easy. Did you try it?
 

FAQ: Calculate the angles in the triangle

How do you find the angles in a triangle?

To find the angles in a triangle, you can use the formula: angle = arccos((a^2 + b^2 - c^2) / 2ab), where a, b, and c are the lengths of the sides of the triangle.

Can you use any formula to find the angles in a triangle?

There are a few different formulas that can be used to find the angles in a triangle, depending on the information you have about the triangle. Some common formulas include the Law of Cosines and the Law of Sines.

What is the sum of the angles in a triangle?

The sum of the angles in a triangle is always 180 degrees. This is known as the Triangle Sum Theorem.

Can you find the angles in a triangle if you only know the lengths of two sides?

Yes, you can use the formula: angle = arccos((a^2 + b^2 - c^2) / 2ab) to find the angles in a triangle if you know the lengths of two sides. You will also need to know the length of the third side to calculate the angles.

Is it possible for a triangle to have more than one obtuse angle?

No, it is not possible for a triangle to have more than one obtuse angle. An obtuse angle is defined as an angle that measures greater than 90 degrees, and since the sum of the angles in a triangle is 180 degrees, there can only be one angle that is greater than 90 degrees.

Back
Top