Answer: 1, 2, 5
Explanation:
The first equation is true because angles in a triangle add to 180 degrees.
The second equation is true because both sides equal 180 degrees (left hand side is a straight angle, right hand side is the sum of angles in a triangle)
The third equation is not true because z = 180 - y, and 180-y+w+z is not 180.
The fourth equation is not true because z=180-y, and 180-y=w+y is not always true.
The fifth equation is true by the exterior angle theorem.