document.write( "Question 26933: how would you do substitution? i don't get it. i need it to be like broke down more like step by step. \n" ); document.write( "
Algebra.Com's Answer #14671 by elima(1433)\"\" \"About 
You can put this solution on YOUR website!
Here's an example I'll use while I try and explain it;
\n" ); document.write( "2x-9y=1
\n" ); document.write( "x-4y=1
\n" ); document.write( "First you need to solve one of the equations for either x or y, we will solve the second one for x;
\n" ); document.write( "x-4y=1
\n" ); document.write( "x=1+4y
\n" ); document.write( "Substitute this value of x in the frist equation;
\n" ); document.write( "2x-9y=1
\n" ); document.write( "2(1+4y)-9y=1
\n" ); document.write( "Distribute the 2:
\n" ); document.write( "2+8y-9y=1
\n" ); document.write( "Add like terms;
\n" ); document.write( "2-y=1
\n" ); document.write( "Subtract 2 from both sides;
\n" ); document.write( "-y=1
\n" ); document.write( "You do not want to leave y negative, so you need to divide both sides by -1;
\n" ); document.write( "y=-1
\n" ); document.write( "Now that you have y, substitue that value in the second equation;
\n" ); document.write( "x-4y=1
\n" ); document.write( "x-4(-1)=1
\n" ); document.write( "x-4=1
\n" ); document.write( "x=1+4
\n" ); document.write( "x=5
\n" ); document.write( "Now you have both y and x;
\n" ); document.write( "x=5
\n" ); document.write( "y=-1
\n" ); document.write( "Hope this helps!
\n" ); document.write( "=) \n" ); document.write( "
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