In which diagram do angles 1 and 2 form a linear pair?
Linear pairs form a straight angle (180 degrees) when they are put together.
Answer: angle1 and 2 in option b forms a linear pair.
Angle 1 and Angle 2 are a linear pair, if Angle 1 + Angle 2 = 180o
Two angles are said to form a linear pair if they add up to 180 degrees.
(a) 50° + 40° = 90°
Since the sum of angles is not equal to 90°, the angles 50° and 40° do not form a linear pair.
(b) 79° + 101° = 180°
Since the sum of angles is equal to 180°, the angles 79° +and 101° form a linear pair.
So, the angles in part (b) form a linear pair.