document.write( "Question 125832This question is from textbook Algebra I
\n" ); document.write( ": This is my son'd hoework assignment, in the back of the book on page 803 in the extra practice section he has to solve proble # 18using linear combinations to solve linear equations. The problem is:\r
\n" ); document.write( "\n" ); document.write( "3x+7y=-1
\n" ); document.write( "7y=-6x\r
\n" ); document.write( "\n" ); document.write( "If I rearrange the equation to solve it looks like this:\r
\n" ); document.write( "\n" ); document.write( " 3x+7y=-1
\n" ); document.write( "-6x-7y=?\r
\n" ); document.write( "\n" ); document.write( "Now what do we do?
\n" ); document.write( "

Algebra.Com's Answer #92218 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
You're almost there
\n" ); document.write( "\"+3x+%2B+7y+=+-1\"
\n" ); document.write( "\"-6x+-+7y+=+0\"
\n" ); document.write( "In the 2nd equation, you subtracted \"7y\" from both sides, and
\n" ); document.write( "that left \"0\" on one side as you can see
\n" ); document.write( "Now just add the 2 equations
\n" ); document.write( "\"-3x+=+-1\"
\n" ); document.write( "\"x+=+1%2F3\"
\n" ); document.write( "substitute this answer in either equation to find \"y\"
\n" ); document.write( "\"-6%281%2F3%29+-+7y+=+0\"
\n" ); document.write( "\"-2+-+7y+=+0\"
\n" ); document.write( "\"7y+=+-2\"
\n" ); document.write( "\"y+=+-%282%2F7%29\"
\n" ); document.write( "check:
\n" ); document.write( "\"+3x+%2B+7y+=+-1\"
\n" ); document.write( "\"-6x+-+7y+=+0\"
\n" ); document.write( "\"3%281%2F3%29+%2B+7%28-%282%2F7%29%29+=+-1\"
\n" ); document.write( "\"1+-+2+=+-1\"
\n" ); document.write( "\"-1+=+-1\"
\n" ); document.write( "OK
\n" ); document.write( "and you can check other one
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