document.write( "Question 503725: Solve using elimination or substitution 4x-7y =-16;6x+3y = 30?
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Algebra.Com's Answer #339388 by oberobic(2304) $\"\"$ $\"About$

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4x -7y = -16
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\n" ); document.write( "Multiply the first equation by 3 and the second equation by 2, then subtract to eliminate the 'x' terms.
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\n" ); document.write( "12x -21y = -48
\n" ); document.write( "12x +6y = 60
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\n" ); document.write( "-27y = -108
\n" ); document.write( "y = 4
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\n" ); document.write( "substitute y=4 into first equation
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\n" ); document.write( "4x -7(4) = -16
\n" ); document.write( "4x = -16 +28
\n" ); document.write( "4x = 12
\n" ); document.write( "x = 3
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\n" ); document.write( "Always check your work.
\n" ); document.write( "Substitute these values in the second equation.
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\n" ); document.write( "6x +3y = 30
\n" ); document.write( "6(3) = 18
\n" ); document.write( "3(4) = 12
\n" ); document.write( "18+12 = 30
\n" ); document.write( "Correct.
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\n" ); document.write( "Answer: x=3, y=4
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\n" ); document.write( "Done. \n" ); document.write( "

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