document.write( "Question 6245: (I am trying to understand my sons home work )
\n" ); document.write( "how do we solve systems by subtitution? \n" ); document.write( "

Algebra.Com's Answer #3403 by xcentaur(357) $\"\"$ $\"About$

You can put this solution on YOUR website!
Solving systems by substitution is one out of many methods of obtaining values that satisfy the given system of equations.
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For example,
\n" ); document.write( "x+y=10......[1]
\n" ); document.write( "3x+4y=45....[2]
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\n" ); document.write( "To solve this system by sbstitution,we would need to go about it like this:
\n" ); document.write( "x+y=10
\n" ); document.write( "x=(10-y)....(*)
\n" ); document.write( "Substituting this value of x in the second equation we get,
\n" ); document.write( "3(10-y)+4y=45
\n" ); document.write( "30-3y+4y=45
\n" ); document.write( "30+y=45
\n" ); document.write( "y=45-30=15
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\n" ); document.write( "then x=10-15=-5,y=15 for this example.
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Thus you can solve a system by substitution.Hope this helps,good luck.
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