Question

Roxanne is measuring the diameter and the radius of different-sized circles. A circle with a 1-inch radius has a diameter of 2 inches. A circle with a 3-inch radius has a diameter of 6 inches.
In this relationship, x represents the radius in inches, and y represents the diameter in inches.
Graph two points for this relationship and the line passing through them.

Answer 1

Plot the points (1, 2) and (3, 6) on the xy-plane. Draw the straight line through them — it also goes through (0,0). The equation of the line is y = 2x (slope = 2).