2013 AMC 10B Problems/Problem 14
Contents
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 | |
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