document.write( "Question 74478: The lines described by 3x-y=17, 2x+5y=17, x+2y=a+b, and x-y=3b-5a all pass through the same point. What is the ratio of a to b? \n" ); document.write( "
Algebra.Com's Answer #53467 by scott8148(6628)\"\" \"About 
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At that point, the x and y values are the same in all the equations. Using the first two equations, you can find values for x and y; and then use those values in the third and fourth equations to find a and b.\r
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\n" ); document.write( "\n" ); document.write( "From first equation: \"y=3x-17\"\r
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\n" ); document.write( "\n" ); document.write( "Substituting into second equation: \"2x%2B5%2A%283x-17%29=17\"\r
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\n" ); document.write( "\n" ); document.write( " so \"x=6\" and from first equation \"y=1\"\r
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\n" ); document.write( "\n" ); document.write( "Using third equation: \"8=a%2Bb\" so \"a=8-b\"\r
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\n" ); document.write( "\n" ); document.write( "Substituting into fourth equation: \"5=3b-5%2A%288-b%29\"\r
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\n" ); document.write( "\n" ); document.write( " so \"b=45%2F8\" and from third equation \"a=19%2F8\"\r
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\n" ); document.write( "\n" ); document.write( "The ratio of a to b is 19:45
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