Let's call the missing angles Z and P. And Z + P = 180 and so P = Z - 134 as well as Angle Z = P + 134. 180 = 2P + 134 Now subtract 134 on both sides of the equal sign. 46 = 2P Now divide both sides of the equal sign by 2 23 = P Now we have P = 23. 180 - 23 (which is P) = 157 So Z is 157 and to check we just put it like this 157 - 134 = 23 Yes it's correct. The angles are 23 degrees and 157 degrees.