The measure of the angles of a triangle add up to 180 degrees.
Therefore, for this case we have the following equation:
45 + 73 + x = 180
Where,
x: is the unknown angle
Clearing x we have:
x = 180-45-73
x = 62 degrees
Answer:
the 3rd angle measure if the other two angles are 45 ° and 73 ° is:
x = 62 degrees