document.write( "Question 314969: How would you do Subsituion method for 4x=720-3y and 5y=12x? \n" ); document.write( "

Algebra.Com's Answer #225301 by solver91311(24713) $\"\"$ $\"About$

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\n" ); document.write( "\n" ); document.write( "I would divide both sides of the second equation by 5 and substitute the resulting expression in x for y in the first equation.\r
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\n" ); document.write( "\n" ); document.write( "Something like this:\r
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\n" ); document.write( "\n" ); document.write( "And then I would solve for

. As soon as I had a value for

I would substitute that back into either of the original equations so that I could solve for

. But then again, that's just me. Someone else might do it differently. There are several other valid ways.\r
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\n" ); document.write( "\n" ); document.write( "John
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