Question

Step 1: m∠x + m∠y + m∠z = 180 degrees (sum of angles of a triangle)
Step 2: m∠w − m∠z = 90 degrees (corresponding angles)
Step 3: Therefore, m∠x + m∠y + m∠z = m∠w + m∠z
Step 4: So, m∠x + m∠y = m∠w

In which step did the student first make a mistake and how can it be corrected?
Step 1; it should be m∠x + m∠y + m∠z = 180 degrees (sum of corresponding angles) Step 2; it should be m∠w + m∠z = 180 degrees (supplementary angles) Step 1; it should be m∠x + m∠y + m∠z = 90 degrees (corresponding angles) Step 2; it should be m∠w + m∠z = 90 degrees (alternate exterior