Step 1: Recall exterior Angle Theorem

NOTE: The measure of an exterior angle of a triangle equals the sum of the two remote interior angle measures.

Step 2: Find the remote interior angle measurements of the triangle

NOTE: Angles opposite to the required exterior angle

Step 3: Add the two remote interior equations measures.

        EXAMPLE:  = v - 49 + v

                            = 2v - 49

Step 4: Set up an equation equal to an exterior angle  

EXAMPLE: v + 46 = 2v - 49  

                      v - 2v = - 49 - 46

                          -v = - 95

                            v = 95                  

Step 5: Substitute the v (variable) value in the given linear equation to know the exact angles

EXAMPLE: v - 49 = 95 -  49 = 46

                        v = 95

                    v + 46 = 95 + 46 = 141