I need help with the slope of this line.

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angle measure.

What are “like terms”? why can we only add like terms?

Which statement explains how you could use coordinate geometry to prove the opposite sides of a quadrilateral are congruent? a. use the slope formula to prove the slopes of the opposite sides are the same. b. use the slope formula to prove the slopes of the opposite sides are opposite reciprocals. c. use the distance formula to prove the lengths of the opposite sides are the same. d. use the distance formula to prove the midpoints of the opposite sides are the same.