2013 AMC 10B Problems/Problem 14
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
.