document.write( "Question 238526: Substitution method\r
\n" ); document.write( "\n" ); document.write( "6x+2y-4=0 and 10x+7y= -8 \n" ); document.write( "

Algebra.Com's Answer #175354 by College Student(505) $\"\"$ $\"About$

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To solve by substitution:
\n" ); document.write( "1. Leave first equation alone for now.
\n" ); document.write( "2. Solve for y on the second equation.
\n" ); document.write( "3. Plug in this value into the first eqn to find x
\n" ); document.write( "4. Once you know the x value, plug it again in the forst equation to find y.
\n" ); document.write( ".
\n" ); document.write( "Problem:
\n" ); document.write( " $\"6x%2B2y-4=0\"$
\n" ); document.write( " $\"10x%2B7y=-8\"$
\n" ); document.write( ".
\n" ); document.write( " $\"10x%2B7y=-8\"$
\n" ); document.write( " $\"7y=-8-10x\"$
\n" ); document.write( " $\"y=%28-8-10x%29%2F7\"$
\n" ); document.write( ".
\n" ); document.write( " $\"6x%2B2%28%28-8-10x%29%2F7%29-4=0\"$
\n" ); document.write( " $\"6x%2B%28%28-16-20x%29%2F7%29-4=0\"$ ... now multiply by 7 to get rid of fraction
\n" ); document.write( " $\"7%2A6x%2B7%2A%28%28-16-20x%29%2F7%29-4%2A7=0\"$
\n" ); document.write( " $\"42x-16-20x-28=0\"$ ... now combine like terms
\n" ); document.write( " $\"22x=16%2B28\"$
\n" ); document.write( " $\"x=44%2F22\"$
\n" ); document.write( " $\"x=2\"$
\n" ); document.write( ".
\n" ); document.write( " $\"6x%2B2y-4=0\"$
\n" ); document.write( " $\"6%282%29%2B2y-4=0\"$
\n" ); document.write( " $\"12%2B2y-4=0\"$
\n" ); document.write( " $\"2y=-8\"$
\n" ); document.write( " $\"y=-%288%2F2%29\"$
\n" ); document.write( " $\"y=-4\"$
\n" ); document.write( ".
\n" ); document.write( "Here are your answers: $\"x=2\"$ and $\"y=-4\"$ \r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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