Given: Prove: Line AD is congruent to Line DB

How can you decide witch operations to use to slice a two step equation

Aperpendicular bisector, cd is drawn through point con ab if the coordinates of point a are (-3, 2) and the coordinates of point b are (7,6), the x-intercept of cd is point lies on cd.

Erin bought christmas cards for $2 each to send to her family and friends. which variable is the dependent variable?