Two concentric circles have radii x and y, where y > x. The area between the circles is at least 10 square units.
(a) Write a system of inequalities that describes the constraints on the circles.
(b) Use a graphing utility to graph the system of inequalities in part (a). Graph the line y = x in the same viewing window.
(c) Identify the graph of the line in relation to the boundary of the inequality. Explain its meaning in the context of the problem.