document.write( "Question 511319: Solve the system of equations using the substitution method. y=3x+1, 3y-7x=9 \n" ); document.write( "

Algebra.Com's Answer #342156 by oberobic(2304) $\"\"$ $\"About$

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y=3x+1.
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\n" ); document.write( "substitute for y
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\n" ); document.write( "\n" ); document.write( "3(3x+1) -7x = 9
\n" ); document.write( "9x +3 -7x = 9
\n" ); document.write( "2x = 6
\n" ); document.write( "x = 3
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\n" ); document.write( "substitute for x
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\n" ); document.write( "y =3(3) +1
\n" ); document.write( "y = 10
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\n" ); document.write( "check using 3y-7x = 9
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\n" ); document.write( "3y -7x = ??
\n" ); document.write( "3(10) -7(3) = 30 -21 = 9
\n" ); document.write( "correct
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\n" ); document.write( "Answer: x=3, y=10
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\n" ); document.write( "Done. \n" ); document.write( "

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