Answer:
60 degrees
Explanation:
The sum of the interior angles of a triangle are 180. The bottom triangle give you two of the angle measurements (43 and 35) Take 180 - 43 -35 = 102. Angle E is 102. Vertical angles are congruent so that mean that we can use that to find angle a. Again, the sum of the interior angles adds up to 180. 180 - 102 - 18 gives us the measurement of angle a (60)