2013 AMC 10B Problems/Problem 14
Contents
[hide]Problem
Define . Which of the following describes the set of points for which ?
Solution
and . Therefore, we have the equation Factoring out a gives Factoring both sides further, . It follows that if , , or , both sides of the equation equal 0. By this, there are 3 lines (, , or ) so the answer is .
Solution 2
Following from the previous solution, . Then, . Factoring, . Now, the solutions are obviously , , or , which each correspond to a line. Thus, the answer is .
See also
2013 AMC 10B (Problems • Answer Key • Resources) | ||
Preceded by Problem 13 |
Followed by Problem 15 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
All AMC 10 Problems and Solutions |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.