document.write( "Question 870721: you can order 10 shirts for $60 from a certain mail order company. From that same company you can get 20 shirts for $100. I cant find the expression! i know its in y=mx+b format but i cant figure it out. \n" ); document.write( "

Algebra.Com's Answer #525087 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
Solve for $\"m\"$ and $\"b\"$
\n" ); document.write( "1. $\"60=m%2810%29%2Bb\"$
\n" ); document.write( "2. $\"100=m%2820%29%2Bb\"$
\n" ); document.write( "Subtract eq. 1 from eq. 2,
\n" ); document.write( " $\"100-60=20x%2Bb-10x%2Bb\"$
\n" ); document.write( " $\"40=10m\"$
\n" ); document.write( " $\"m=4\"$
\n" ); document.write( "Now user either equation to solve for $\"b\"$
\n" ); document.write( " $\"%2820%29%284%29%2Bb=100\"$
\n" ); document.write( " $\"b=20\"$
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\n" ); document.write( " $\"highlight%28y=4x%2B20%29\"$
\n" ); document.write( "where $\"x\"$ is the number of shirts, $\"y\"$ is your cost.\r
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