document.write( "Question 103564: Solve the system by substitution. Help me please.\r
\n" ); document.write( "\n" ); document.write( "x + y = 12
\n" ); document.write( " y = 2x \n" ); document.write( "

Algebra.Com's Answer #75361 by ptaylor(2198) $\"\"$ $\"About$

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\n" ); document.write( "x + y = 12---------------eq1
\n" ); document.write( "y = 2x ----------------------eq2\r
\n" ); document.write( "\n" ); document.write( "Lets substitute y=2x from eq2 into eq1 and we get:\r
\n" ); document.write( "\n" ); document.write( "x+2x=12 collect like terms\r
\n" ); document.write( "\n" ); document.write( "3x=12 divide both sides by 3\r
\n" ); document.write( "\n" ); document.write( "x=4\r
\n" ); document.write( "\n" ); document.write( "Now we can substitute x=4 into eq2 and we get:\r
\n" ); document.write( "\n" ); document.write( "y=2*4=8\r
\n" ); document.write( "\n" ); document.write( "So our answer is:\r
\n" ); document.write( "\n" ); document.write( "x=4 and
\n" ); document.write( "y=8\r
\n" ); document.write( "\n" ); document.write( "CK
\n" ); document.write( "From eq1:
\n" ); document.write( "x+y=12
\n" ); document.write( "4+8=12
\n" ); document.write( "12=12
\n" ); document.write( "From eq2:
\n" ); document.write( "y=2x
\n" ); document.write( "8=2*4
\n" ); document.write( "8=8\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Hope this helps---ptaylor\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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