document.write( "Question 347672: Please help me solve this equation by method of substitution y=x(3) I tried substituting 14 for x. The main equation is x + y = 56 where y =x(3). After the substitution I got 14 + 42 = 56 and 42=14(3). Is that correct? \n" ); document.write( "

Algebra.Com's Answer #248513 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
No, that's not correct.
\n" ); document.write( "How did you come up with $\"14\"$ ?
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\n" ); document.write( "1. $\"y=3x\"$
\n" ); document.write( "2. $\"x%2By=56\"$
\n" ); document.write( "Now substitute eq. 1 into eq. 2, that's where the substitution comes in.
\n" ); document.write( " $\"x%2B%283x%29=56\"$
\n" ); document.write( " $\"4x=56\"$
\n" ); document.write( " $\"x=14\"$
\n" ); document.write( "That's where the $\"14\"$ comes from.
\n" ); document.write( "Now use either equation and the result for $\"x\"$ to find $\"y\"$ .
\n" ); document.write( "From eq. 1,
\n" ); document.write( " $\"y=3%2814%29\"$
\n" ); document.write( " $\"y=42\"$
\n" ); document.write( "So the solution is $\"x=14\"$ and $\"y=42\"$ .
\n" ); document.write( "You verify the solution by plugging it back into your original equations.
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