document.write( "Question 53284: Will you please solve the system by subtraction
\n" ); document.write( "3x-y=-7
\n" ); document.write( "x+y=-9
\n" ); document.write( "thankyou \n" ); document.write( "
Algebra.Com's Answer #35551 by funmath(2933)\"\" \"About 
You can put this solution on YOUR website!
You can solve this by adding the two equations together and eliminating the y's then solve for x:
\n" ); document.write( "3x-y=-7
\n" ); document.write( "x+y=-9
\n" ); document.write( "_________
\n" ); document.write( "4x+0y=-16
\n" ); document.write( "4x=-16
\n" ); document.write( "4x/4=-16/4
\n" ); document.write( "x=-4
\n" ); document.write( "-------------------
\n" ); document.write( "Now substitute x=-4 into the second equation (it's the easier of the two) and solve for y:
\n" ); document.write( "-4+y=-9
\n" ); document.write( "+4-4+y=-9+4
\n" ); document.write( "y=-5
\n" ); document.write( "-------------------
\n" ); document.write( "Your solution is: (-4,-5)
\n" ); document.write( "-------------------------
\n" ); document.write( "You can check this by substituting these values into both equations and see if it checks:
\n" ); document.write( "3(-4)-(-5)=-7
\n" ); document.write( "-12+5=-7
\n" ); document.write( "-7=-7 I think we're right!
\n" ); document.write( "(-4)+(-5)=-9
\n" ); document.write( "-9=-9 I know we're right!!!!! \n" ); document.write( "
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