This trigonometry video is about How to solve the value of X in where an Exterior angle theorem was used for finding the value of X which was the missing angle. Two triangles are given back to back each other. They are not right triangles; however, few consecutive interior angles are given for both triangles. To find the missing angle, the angle sum theorem was applied to find the value of the exterior angle. We know the summation angle of a triangle is 180 degrees. If two angles are given in geometry, the third missing angle of a right triangle or another triangle can be calculated. In this case, the missing remote interior angles can give the angle of the second triangle. The intersecting lines separate 180 degrees into two angles if one is known then another can be calculated easily. That means initially supplementary angle is required to solve this angle of the triangle. Only someone needs the trigonometry basic knowledge to solve the values of x. #Geometry #ExteriorAngles #Trigonometry #Triangle Watch other interesting videos on Matescium Imaginary Number Prove that 1+1=0, Kick Out the Rules of Mathematics: https://www.youtube.com/watch?v=1rv1qQQ5cNI Upgrade RAM and get a faster computer: https://www.youtube.com/watch?v=8yE_PaaU-6Q Thanks for watching it.