document.write( "Question 68775: Solve the system of equations using the substitution method.
\n" ); document.write( "If the answer is a unique solution, present it as an ordered pair: (x, y). If not, specify whether the answer is “no solution” or “infinitely many solutions.”
\n" ); document.write( "-4x + y = 8
\n" ); document.write( "2x + 3y = -1 \n" ); document.write( "

Algebra.Com's Answer #49057 by rmromero(383) $\"\"$ $\"About$

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document.write( "Here are the Steps using Substition method
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document.write( "1. In either equation, solve for one variable in terms of the other.
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document.write( "     -4x + y = 8
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document.write( "           y = 4x + 8\r
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document.write( "2. Substitute 4x + 8 for y in the other equation. Solve x.
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document.write( "             2x + 3y = -1 
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document.write( "      2x + 3(4x + 8) = -1
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document.write( "       2x + 12x + 24 = -1
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document.write( "            14x + 24 = -1
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document.write( "                 14x = -25
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document.write( "                   x = -25/14 \r
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document.write( "3. Substitute the result from step 2 in either equation 2x + 3y = -1. 
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document.write( "   Solve for the other variable.
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document.write( "       -4x + y = 8 , x = -25/14
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document.write( "-4(-25/14) + y = 8
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document.write( "    100/14 + y = 8
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document.write( "             y = 12/14\r
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document.write( "4. Check the solution in both original equations.\r
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document.write( "             2x + 3y = -1, x = -25/14, y = 12/14
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document.write( "2(-25/14) + 3(12/14) = -1 
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document.write( "      -50/14 + 36/14 = -1
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document.write( "              -14/14 = -1
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document.write( "                  -1 = -1 ----------->True\r
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document.write( "             -4x + y = 8, x = -25/14, y = 12/14 
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document.write( "-4(-25/14) + (12/14) = 8
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document.write( "      100/14 + 12/14 = 8
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document.write( "              112/14 = 8
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document.write( "                   8 = 8  ----------->>True\r
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document.write( "There is a unique solution, (-25/14, 12/14)\r
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