For each scenario, complete each statement and its justification by dragging the appropriate words, phrases, or statements into the answer boxes. Click on the “Check answer” box to see if you are correct. Record your statements and the justifications.

Based on what you observe about ∠A, ∠B, and ∠ACD, what statement can be made about the relationship between an exterior angle and the remote interior angles of a triangle?

Image shows triangle ABC with angle A equal to 60 degrees, angle B equal to 80 degrees and the exterior angle at C equal to 140 degrees

Drag these into the blanks below to complete each statement and justification.

Interactive exercise. Assistance may be required.