Difference between revisions of "2021 Fall AMC 12A Problems/Problem 13"

(Created page with "==Problem 13== The angle bisector of the acute angle formed at the origin by the graphs of the lines <math>y = x</math> and <math>y=3x</math> has equation <math>y=kx.</math> W...")
 
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The angle bisector of the acute angle formed at the origin by the graphs of the lines <math>y = x</math> and <math>y=3x</math> has equation <math>y=kx.</math> What is <math>k?</math>
 
The angle bisector of the acute angle formed at the origin by the graphs of the lines <math>y = x</math> and <math>y=3x</math> has equation <math>y=kx.</math> What is <math>k?</math>
  
<math>\textbf{(A)} \: \frac{1+\sqrt{5}}{2} \qquad \textbf{(B)} \: \frac{1+\sqrt{7}}{2} \qquad \textbf{(C)} \: \frac{2+\sqrt{3}}{2} \qquad \textbf{(D)} \: 2\qquad \textbf{(E)} \: \frac{2+\sqrt{5}}{2}</math>
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<math>\textbf{(A)} \ \frac{1+\sqrt{5}}{2} \qquad \textbf{(B)} \ \frac{1+\sqrt{7}}{2} \qquad \textbf{(C)} \ \frac{2+\sqrt{3}}{2} \qquad \textbf{(D)} \ 2\qquad \textbf{(E)} \ \frac{2+\sqrt{5}}{2}</math>
  
 
==Solution==
 
==Solution==
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~MRENTHUSIASM
 
~MRENTHUSIASM
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==See Also==
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{{AMC12 box|year=2021 Fall|ab=A|num-b=12|num-a=14}}
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{{MAA Notice}}

Revision as of 20:55, 23 November 2021

Problem 13

The angle bisector of the acute angle formed at the origin by the graphs of the lines $y = x$ and $y=3x$ has equation $y=kx.$ What is $k?$

$\textbf{(A)} \ \frac{1+\sqrt{5}}{2} \qquad \textbf{(B)} \ \frac{1+\sqrt{7}}{2} \qquad \textbf{(C)} \ \frac{2+\sqrt{3}}{2} \qquad \textbf{(D)} \ 2\qquad \textbf{(E)} \ \frac{2+\sqrt{5}}{2}$

Solution

IN PROGRESS. APPRECIATE IT IF NO EDITS. THANKS.

~MRENTHUSIASM

See Also

2021 Fall AMC 12A (ProblemsAnswer KeyResources)
Preceded by
Problem 12
Followed by
Problem 14
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 12 Problems and Solutions

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