document.write( "Question 107332This question is from textbook Introductory and Intermediate Algebra
\n" ); document.write( ": I'm not really clear on how to set up this type of problem. Any insight would be greatly appreciated. x+y=12
\n" ); document.write( " y=3x \n" ); document.write( "

Algebra.Com's Answer #78127 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
1. $\"x%2By=12\"$
\n" ); document.write( "2. $\"y=3x\"$
\n" ); document.write( "You have two equations with two unknowns, a linear system of equations.
\n" ); document.write( "You should be able to solve for x and y.
\n" ); document.write( "Using equation 2 and substitute into equation 1.
\n" ); document.write( "1. $\"x%2By=12\"$
\n" ); document.write( " $\"x%2B%283x%29=12\"$
\n" ); document.write( " $\"4x=12\"$
\n" ); document.write( " $\"x=3\"$
\n" ); document.write( "Now substitute into 2.
\n" ); document.write( "2. $\"y=3x\"$
\n" ); document.write( " $\"y=3%283%29\"$
\n" ); document.write( " $\"y=9\"$
\n" ); document.write( "Check your answers with your original equations.
\n" ); document.write( "1. $\"x%2By=12\"$
\n" ); document.write( " $\"3%2B9=12\"$
\n" ); document.write( " $\"12=12\"$
\n" ); document.write( "True statement. Good answer.
\n" ); document.write( "2. $\"y=3x\"$
\n" ); document.write( " $\"9=3%283%29\"$
\n" ); document.write( " $\"9=9\"$
\n" ); document.write( "True statement. Good answer.
\n" ); document.write( "x=3 and y=9. \n" ); document.write( "

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