12 - 23 = -11
-11 + 1,345 = 1,334
1,334/123 = 10.85
Definition of an exterior angle
At each vertex of a triangle, an exterior angle of the triangle may be formed by extending ONE SIDE of the triangle. See picture below.
Calculating the Angles
We can use equations to represent the measures of the angles described above. One equation might tell us the sum of the angles of the triangle. For example,
x + y + z = 180
You have to move both decimals over and then divide. So the answer is 25.
