Question

Use the Angle Addition Postulate to find the measure of each angle.

Answer 1

For number 15 and 16, you just have to find the absolute difference between the two points along the calibration of the protractor.

15. ∠BXC = |B - C| = |140° - 110°| = 30°
16. ∠BXE = |B - E| = |140° - 30°| = 110°

For numbers 20 and 21, apply the Angle Addition Postulate. This is when you add the individual interior angles to equate to the total angle.

20. ∠PQS = ∠PQR + ∠RQS
      112° = 72°+ 10x°
       x = 4

21. ∠KLM = ∠KLN + ∠NLM
      135° = 47°+ 16y°
       y = 5.5