A diagram and information about it is provided. A student is trying to figure out the measure of angel EDF. Complete the students thought process in green boxes below. Angle 1 is 60 because

Answer 1

it is a straight angle and straight angles always measure 180°.

Angle 1 = 180°

Angle DCE is a vertical angle to angle 1, so it must also measure 60° because vertical angles are congruent.

Angle DCE = 60°

Since angles ACE and DCE are supplementary angles, their measures must add up to 180°.

Angle ACE + Angle DCE = 180°

Angle ACE + 60° = 180°

Subtracting 60 from both sides:

Angle ACE = 180° - 60° = 120°

Now, angle EDF and angle ACE are corresponding angles, and corresponding angles in parallel lines are congruent.

Therefore, Angle EDF = 120°