document.write( "Question 102598: Solve the system by substitution\r
\n" ); document.write( "\n" ); document.write( "x-4y=-19
\n" ); document.write( "-4x-5y=13 \n" ); document.write( "

Algebra.Com's Answer #74607 by MathLover1(20850) $\"\"$ $\"About$

You can put this solution on YOUR website!
I. $\"x-4y=-19+\"$ first find x in this one
\n" ); document.write( "II. $\"-4x-5y=13\"$ \r
\n" ); document.write( "\n" ); document.write( "then we have
\n" ); document.write( " $\"x+=+%284y%29+-+19\"$ now put this in II. and find y
\n" ); document.write( " $\"-%284%294y+\"$ – $\"19\"$ – $\"5y+\"$ = $\"13\"$
\n" ); document.write( " $\"-16y+%2B+76+%96+5y+=+13\"$
\n" ); document.write( " $\"76+%96+13+=+21y\"$
\n" ); document.write( " $\"21y+=+63\"$
\n" ); document.write( " $\"y+=+63%2F21\"$
\n" ); document.write( " $\"y+=+3\"$ \r
\n" ); document.write( "\n" ); document.write( "Now we can calculate x
\n" ); document.write( " $\"x+=+4y+%96+19\"$
\n" ); document.write( " $\"x+=+12+%96+19\"$
\n" ); document.write( " $\"x+=+-7\"$ \r
\n" ); document.write( "\n" ); document.write( "Check:
\n" ); document.write( " $\"x+%96+4y+=+-+19\"$
\n" ); document.write( " $\"-7+%96+4%2A3+=+-19\"$
\n" ); document.write( " $\"-7+-12+=+-19\"$
\n" ); document.write( " $\"-19+=+-19\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"-4x-5y=13\"$
\n" ); document.write( " $\"-4%2A%28-7%29-5%2A3=13\"$
\n" ); document.write( " $\"28-+15=13\"$
\n" ); document.write( " $\"13+=13\"$ \r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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