Angle 1 and Angle 7 are Alternate Interior Angles
Angle 1 and Angle 5 are Corresponding Angles, Angles 5 and 7 are Vertical Angles, so Angle 1 = Angle 7
Angle 1 and Angle 3 are Vertical Angles, Angle 3 and Angle 7 are Corresponding Angles, so Angle 1 = Angle 7
