Problem:
Define . Which of the following describes the set of points for which ?
Answer Choices:
A. a finite set of points
B. one line
C. two parallel lines
D. two intersecting lines
E. three lines
Solution:
The equation is equivalent to . This equation is euivalent to gives . This equation will hold exactly if , or . The solution set consists of : the -axis, the -axis, and the line .
The problems on this page are the property of the MAA's American Mathematics Competitions