document.write( "Question 188887: solving systems of linear equations.solve by substitution\r
\n" ); document.write( "\n" ); document.write( "2x+y=10
\n" ); document.write( "3x-4y=26\r
\n" ); document.write( "\n" ); document.write( "y=2x+3
\n" ); document.write( "3x+2y=6\r
\n" ); document.write( "\n" ); document.write( "solving systems of linear equations.solve by addition elimination\r
\n" ); document.write( "\n" ); document.write( "3x-6y=5
\n" ); document.write( "2x-4y=8\r
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Algebra.Com's Answer #141679 by jojo14344(1513)\"\" \"About 
You can put this solution on YOUR website!

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\n" ); document.write( "Solving systems of linear equations.Solve by substitution
\n" ); document.write( "2x+y=10, EQN 1
\n" ); document.write( "3x-4y=26, EQN 2\r
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\n" ); document.write( "\n" ); document.write( "In EQN 1 we get, \"y=10-2x\"--> EQN 3, substitute in EQN 2\r
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\n" ); document.write( "\n" ); document.write( "\"3x-4%28highlight%2810-2x%29%29=26\"
\n" ); document.write( "\"3x-40%2B8x=26\"
\n" ); document.write( "\"11x=26%2B40=66\" ---->\"cross%2811%29x%2Fcross%2811%29=cross%2866%296%2Fcross%2811%29\"
\n" ); document.write( "\"highlight%28x=6%29\", substitute in EQN 3:\r
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\n" ); document.write( "\n" ); document.write( "\"y=10-2%286%29=10-12=highlight%28-2%29\"\r
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\n" ); document.write( "\n" ); document.write( "Intersect at point (6,-2)
\n" ); document.write( " --->RED, EQN1; GREEN, EQN 2\r
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\n" ); document.write( "\n" ); document.write( "y=2x+3, EQN 1
\n" ); document.write( "3x+2y=6, EQN 2\r
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\n" ); document.write( "\n" ); document.write( "Substitute EQN 1 in EQN 2:
\n" ); document.write( "\"3x%2B2highlight%28%282x%2B3%29%29=6\"
\n" ); document.write( "\"3x%2B4x%2B6=6\"
\n" ); document.write( "\"7x=6-6=0\" ----> \"highlight%28x=0%29\", subst. in EQN 1\r
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\n" ); document.write( "\n" ); document.write( "\"y=2%280%29%2B3\" ----> \"highlight%28y=3%29\"\r
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\n" ); document.write( "\n" ); document.write( "Intersect at point (0,3)
\n" ); document.write( " ---> RED, EQN 1; GREEN, EQN 2\r
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\n" ); document.write( "\n" ); document.write( "Solving systems of linear equations. Solve by addition elimination
\n" ); document.write( "3x-6y=5, EQN 1
\n" ); document.write( "2x-4y=8, EQN 2 \r
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\n" ); document.write( "\n" ); document.write( "Multiply EQN 1 by -4, EQN 2 by 6, and then \"add\":
\n" ); document.write( "\"3x-6y=5\"x\"-4\" ----> \"cross%28-12x%29%2Bcross%2824y%29=-20\"
\n" ); document.write( "\"2x-4y=8\"x\"6\" -----> \"cross%2812x%29-cross%2824y%29=48\"
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\n" ); document.write( " no solution. These lines don't intersect:\r
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\n" ); document.write( "\n" ); document.write( "We'll look for the intercepts:
\n" ); document.write( "In EQN 1, let fy=0
\n" ); document.write( "\"3x-6%280%29=5\" ---> \"cross%283%29x%2Fcross%283%29=5%2F3\"
\n" ); document.write( "\"red%28x=5%2F3%29\"
\n" ); document.write( "let fx=0
\n" ); document.write( "\"3%280%29-6y=5\" ---> \"cross%28-6%29y%2Fcross%28-6%29=5%2F-6\"
\n" ); document.write( "\"red%28y=-5%2F6%29\"\r
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\n" ); document.write( "\n" ); document.write( "In EQN 2, let Fy=0
\n" ); document.write( "\"2x-4%280%29=8\" ---> \"cross%282%29x%2Fcross%282%29=cross%288%294%2Fcross%282%29\"
\n" ); document.write( "\"red%28x=4%29\"
\n" ); document.write( "Let fx=0
\n" ); document.write( "\"2%280%29-4y=8\" ---> \"cross%28-4%29y%2Fcross%28-4%29=cross%288%292%2Fcross%28-4%29\"
\n" ); document.write( "\"red%28y=-2%29\"\r
\n" ); document.write( "\n" ); document.write( " ---> RED, EQN 1; GREEN, EQN 2
\n" ); document.write( "Since they line on the same plane they are parallel\r
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\n" ); document.write( "\n" ); document.write( "Thank you,
\n" ); document.write( "Jojo
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