Difference between revisions of "2021 Fall AMC 10B Problems/Problem 17"
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Distinct lines <math>\ell</math> and <math>m</math> lie in the <math>xy</math>-plane. They intersect at the origin. Point <math>P(-1, 4)</math> is reflected about line <math>\ell</math> to point <math>P'</math>, and then <math>P'</math> is reflected about line <math>m</math> to point <math>P''</math>. The equation of line <math>\ell</math> is <math>5x - y = 0</math>, and the coordinates of <math>P''</math> are <math>(4,1)</math>. What is the equation of line <math>m?</math> | Distinct lines <math>\ell</math> and <math>m</math> lie in the <math>xy</math>-plane. They intersect at the origin. Point <math>P(-1, 4)</math> is reflected about line <math>\ell</math> to point <math>P'</math>, and then <math>P'</math> is reflected about line <math>m</math> to point <math>P''</math>. The equation of line <math>\ell</math> is <math>5x - y = 0</math>, and the coordinates of <math>P''</math> are <math>(4,1)</math>. What is the equation of line <math>m?</math> | ||
<math>(\textbf{A})\: 5x+2y=0\qquad(\textbf{B}) \: 3x+2y=0\qquad(\textbf{C}) \: x-3y=0\qquad(\textbf{D}) \: 2x-3y=0\qquad(\textbf{E}) \: 5x-3y=0</math> | <math>(\textbf{A})\: 5x+2y=0\qquad(\textbf{B}) \: 3x+2y=0\qquad(\textbf{C}) \: x-3y=0\qquad(\textbf{D}) \: 2x-3y=0\qquad(\textbf{E}) \: 5x-3y=0</math> | ||
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==See Also== | ==See Also== | ||
{{AMC10 box|year=2021 Fall|ab=B|num-a=18|num-b=16}} | {{AMC10 box|year=2021 Fall|ab=B|num-a=18|num-b=16}} | ||
{{MAA Notice}} | {{MAA Notice}} | ||
Revision as of 12:02, 23 November 2021
Problem
Distinct lines 
and 
lie in the 
-plane. They intersect at the origin. Point 
is reflected about line to point 
, and then is reflected about line to point 
. The equation of line is 
, and the coordinates of are 
. What is the equation of line 
See Also
| 2021 Fall AMC 10B (Problems • Answer Key • Resources) | ||
| Preceded by Problem 16 |
Followed by Problem 18 | |
| 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 | ||
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