document.write( "Question 1189710: In the diagram attached below, Circles M and N are tangent to each other, and to Line AB and Line BC. If Angle ABC=120°, what is the ratio of the radius of Circle M to the radius of circle N\r
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\n" ); document.write( "\n" ); document.write( "Diagram: https://imgur.com/a/4dfUycL
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Algebra.Com's Answer #821185 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "Let r and R be the radii of circles N and M, respectively; the problem asks us to find R/r.

\n" ); document.write( "Draw segment BM, intersecting circle M at D.

\n" ); document.write( "Segment BM bisects angle ABC, so angles ABM and CBM are each 60 degrees.

\n" ); document.write( "Draw segment NE with E the point of tangency of circle N to line BC. Draw segment MF with F the point of tangency of circle M to line BC.

\n" ); document.write( "Triangles BEN and BFM are similar 30-60-90 right triangles.

\n" ); document.write( "The ratio of the hypotenuse to the long leg in a 30-60-90 right triangle is \"2%2Fsqrt%283%29\".

\n" ); document.write( "In triangle BFM, FM is the long leg; the hypotenuse is

\n" ); document.write( "\"MD%2BDN%2BNB=R%2Br%2Br%282%2Fsqrt%283%29%29\"

\n" ); document.write( "So in triangle BFM,

\n" ); document.write( "\"%28R%2Br%2Br%282%2Fsqrt%283%29%29%29%2FR=2%2Fsqrt%283%29\"

\n" ); document.write( "Solve for R/r:

\n" ); document.write( "\"1%2B%28r%2Br%282%2Fsqrt%283%29%29%29%2FR=2%2Fsqrt%283%29\"

\n" ); document.write( "\"%28r%281%2B2%2Fsqrt%283%29%29%29%2FR=2%2Fsqrt%283%29-1=%282-sqrt%283%29%29%2Fsqrt%283%29\"

\n" ); document.write( "The current equation involves r/R on the left; take reciprocals to get an equation involving R/r:

\n" ); document.write( "\"R%2F%28r%281%2B2%2Fsqrt%283%29%29%29=sqrt%283%29%2F%282-sqrt%283%29%29\"

\n" ); document.write( "\"R%2Fr=%28sqrt%283%29%2F%282-sqrt%283%29%29%29%281%2B2%2Fsqrt%283%29%29\"

\n" ); document.write( "\"R%2Fr=%28sqrt%283%29%2F%282-sqrt%283%29%29%29%28%282%2Bsqrt%283%29%29%2Fsqrt%283%29%29\"

\n" ); document.write( "\"R%2Fr=%282%2Bsqrt%283%29%29%2F%282-sqrt%283%29%29\"

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\n" ); document.write( "\"R%2Fr=%287%2B4sqrt%283%29%29%2F%284-3%29\"

\n" ); document.write( "\"R%2Fr+=+7%2B4sqrt%283%29\"

\n" ); document.write( "ANSWER: The ratio of the radius of circle M to the radius of circle N is \"R%2Fr+=+7%2B4sqrt%283%29\"

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