I'm just uncertain about what d is.

complete the paragraph proof.

given: angle 1 and angle 2 are supplementary, and angle 2 and angle 3 are supplementary.

prove: angle 1 ≅ angle 3

by the definition of supplementary angles, angle 1 + angle 2 = ) and angle 2 + angle 3 = (b). then angle one + angle 2 = angle 2 + angle 3 ). subtract angle 2 from each side. you get angle 1 = ), or angle 1 ≅ ).

i think that they are the following.

a is 180 degrees.
b is 180 degrees.
c is 360 degrees.
d
e is angle 3

what do you think d is? do you think i am correct?