document.write( "Question 1056580: Use elimination to solve each system of equations. I have to show all work and write the answer as an (x,y) ordered.\r
\n" ); document.write( "\n" ); document.write( "7x+4y=-4
\n" ); document.write( "5x+8y=28 \n" ); document.write( "

Algebra.Com's Answer #671672 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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7x + 4y =-4
\n" ); document.write( "5x + 8y = 28
\n" ); document.write( ":
\n" ); document.write( "Multiply the first equation by -2, add the 2nd equation
\n" ); document.write( "-14x - 8y = 8
\n" ); document.write( " 5x + 8y = 28
\n" ); document.write( "-----------------
\n" ); document.write( "-9x = 36
\n" ); document.write( "x = 36/-9
\n" ); document.write( "x = -4
\n" ); document.write( "Find y using the 1st equation; replace x with -4
\n" ); document.write( "7(-4) + 4y = -4
\n" ); document.write( "-28 + 4y = -4
\n" ); document.write( "4y = -4 + 28
\n" ); document.write( "4y = 24
\n" ); document.write( "y = 24/4
\n" ); document.write( "y = 6
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check solutions in the 2nd equation; replace x and y
\n" ); document.write( "5(-4) + 8(6) = 28
\n" ); document.write( "-20 + 48 = 28
\n" ); document.write( ":
\n" ); document.write( "-4,6 \n" ); document.write( "

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