document.write( "Question 123873: I do not understand this..I have to write a system of 2 equations in 2 unknowns and solve each system by substitution.\r
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "\n" ); document.write( "thanks so so much \n" ); document.write( "
Algebra.Com's Answer #90892 by applesrbest(7)\"\" \"About 
You can put this solution on YOUR website!
Let Marysville by m and Springfield be s.\r
\n" ); document.write( "\n" ); document.write( "m+s = 25000 -------eqn 1
\n" ); document.write( "0.1m+0.09s = 2380 ----------eqn 2
\n" ); document.write( "From eqn 1: m = 25000-s ---------eqn 3\r
\n" ); document.write( "\n" ); document.write( "Sub eqn 3 into eqn 2:
\n" ); document.write( "(0.1)(25000-s)+0.09s = 2380
\n" ); document.write( "2500-0.01s = 2380
\n" ); document.write( "0.01s = 120
\n" ); document.write( "s = 12000
\n" ); document.write( "Sub s=12000 back into eqn 3:
\n" ); document.write( "m=13000\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "
\n" );