Angle Theorems

Supplementary Angles: The sum of two angles is 180 degrees. If one angle is 50 degree we will found the missing angle by subtracting 50 by 180 we get 130 degrees.

Complementary Angle: The sum of two angles is 90 degrees that means Right Angle. Thus if we want to find a missing angle in it by just given an angle say,30 degrees we will subtract from 90 and thus we get 60 degrees as the missing angle.

Opposite Angle Theorem: Two angle which angles are directly across from each other mathematics. If the angle is 80 degrees then it will be 80 degrees too.

The Sum of the Interior Angles of a Triangle: The sum of all the three angles of interior sides is 180 degrees.

Isosceles Triangle Theorem: It means two of the sides of the same length. Directly down at the bottoms the angles are also equal. Thus the missing angle if we want to know, we already know that two sides are equal thus 50 and 50 are two equal angles and which sums up to 100.thus we subtract it from 180 solution is 80 degrees is the missing angle.

Equilateral Triangles: All of the side lengths are same. Thus all the angles are same. If we divide 180 by 3, we get 60 degree. Thus all angles are 60 degrees.

Exterior Angle Theorem: The Angle which is outside of the triangle, by extending the lines and making angles. For an example if ABC is a triangle and from b we extend a straight line naming it as D Here we know that A+B is equal to C. If the exterior angle is 60 and the one angle in interior is 20 degrees then how to find the missing angle.60-20=40 and that’s the missing angle of the triangle. Because we know that A+B=C thus 20+40 is 60.we just proved it.

Parallel Line Theorem: In parallel lines the corresponding angles are equals.