document.write( "Question 1190081: x+y=30
\n" ); document.write( "3x+4y=100
\n" ); document.write( "Solve for x&y
\n" ); document.write( "There would be___ 3-point questions and ___ 4-point questions
\n" ); document.write( "I need lots of detail on how to do this, please.
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Algebra.Com's Answer #821637 by math_tutor2020(3817)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "Solve the first equation for y
\n" ); document.write( "x+y = 30
\n" ); document.write( "y = 30-x\r
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\n" ); document.write( "\n" ); document.write( "Then plug this into the second equation
\n" ); document.write( "3x+4y = 100
\n" ); document.write( "3x+4( y )= 100
\n" ); document.write( "3x+4( 30-x )= 100\r
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\n" ); document.write( "\n" ); document.write( "At this point we solve for x
\n" ); document.write( "3x+4( 30-x )= 100
\n" ); document.write( "3x+120-4x= 100
\n" ); document.write( "-x+120= 100
\n" ); document.write( "-x= 100-120
\n" ); document.write( "-x = -20
\n" ); document.write( "x = 20\r
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\n" ); document.write( "\n" ); document.write( "Use this to find y
\n" ); document.write( "y = 30-x
\n" ); document.write( "y = 30-20
\n" ); document.write( "y = 10\r
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\n" ); document.write( "\n" ); document.write( "Summary:
\n" ); document.write( "x = 20 and y = 10
\n" ); document.write( "The two lines cross at (20,10).
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