Russo and Frederica want to find out if the parallelogram formed by connecting points
A, B, C, and D is a rhombus.
Russo's plan:
• Use the distance formula to find the lengths of the sides.
• See if the sides are all the same length.
Frederica's plan:
• Find the slopes of the two diagonals.
• See if the two slopes are negative reciprocals of each other.
Which student's plan will work?