document.write( "Question 74726: Find values for m and b in the following system so that the solution to the system is (-3, 4).
\n" ); document.write( "5x+7y=b
\n" ); document.write( "mx+y=22
\n" ); document.write( " \n" ); document.write( "

Algebra.Com's Answer #53702 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"5x%2B7y=b\"$ Plug in (-3,4) into the first equation
\n" ); document.write( " $\"5%28-3%29%2B7%284%29=b\"$ Solve for b
\n" ); document.write( " $\"-15%2B28=b\"$
\n" ); document.write( " $\"b=13\"$
\n" ); document.write( "Now plug in (-3,4) into the 2nd equation
\n" ); document.write( " $\"m%28-3%29%2B%284%29=22\"$
\n" ); document.write( " $\"-3m%2B4=22\"$
\n" ); document.write( " $\"-3m=18\"$
\n" ); document.write( " $\"m=-6\"$
\n" ); document.write( "So m=-6. Use this info to complete the system of equations
\n" ); document.write( " $\"5x%2B7y=13\"$
\n" ); document.write( " $\"-6x%2By=22\"$
\n" ); document.write( "

\n" ); document.write( "Check:
\n" ); document.write( " $\"5x%2B7y=13\"$ if we plug in (-3,4) it should satisfy the sytem
\n" ); document.write( " $\"-6x%2By=22\"$
\n" ); document.write( " $\"5%28-3%29%2B7%284%29=13\"$
\n" ); document.write( " $\"-6%28-3%29%2B%284%29=22\"$
\n" ); document.write( " $\"-15%2B28=13\"$
\n" ); document.write( " $\"18%2B4=22\"$
\n" ); document.write( " $\"13=13\"$ works
\n" ); document.write( " $\"22=22\"$ works \n" ); document.write( "

\n" );