document.write( "Question 214684: Solve linear system
\n" ); document.write( "-4x-3y=-27
\n" ); document.write( "-4x+4y=8
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Algebra.Com's Answer #162117 by drj(1380)\"\" \"About 
You can put this solution on YOUR website!
Solve linear system\r
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\n" ); document.write( "\n" ); document.write( "\"-4x-3y=-27\" Equation A\r
\n" ); document.write( "\n" ); document.write( "\"-4x%2B4y=8\" Equation B\r
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\n" ); document.write( "\n" ); document.write( "Step 1. Subtract Equation B from Equation A to get rid of x terms to get\r
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\n" ); document.write( "\n" ); document.write( "\"-7y=-35\"\r
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\n" ); document.write( "\n" ); document.write( "Step 2. Divide by -7 to both sides to get\r
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\n" ); document.write( "\n" ); document.write( "\"-7y%2F7=-35%2F-7\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=5\"\r
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\n" ); document.write( "\n" ); document.write( "Step 3. Substitute y=5 into one of the equation to get x\r
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\n" ); document.write( "\n" ); document.write( "{{-4x-3(5)=-27}}}\r
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\n" ); document.write( "\n" ); document.write( "\"-4x-15=-27\"\r
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\n" ); document.write( "\n" ); document.write( "Step 4. Add 15 to both sides to get x-terms on the left side and numbers on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x-15%2B15=-27%2B15\"\r
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\n" ); document.write( "\n" ); document.write( "\"-4x=-12\"\r
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\n" ); document.write( "\n" ); document.write( "Step 5. Divide by -4 to both sides of equation to get x\r
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\n" ); document.write( "\n" ); document.write( "\"-4x%2F-4=-12%2F-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=3\"\r
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\n" ); document.write( "\n" ); document.write( "Step 6. ANSWER: Solution is x=3 and y=5\r
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\n" ); document.write( "\n" ); document.write( "We can also solve the equation using SUBSTITUTION:\r
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Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
\n" ); document.write( " \"+system%28+%0D%0A++++-4%5Cx+%2B+-3%5Cy+=+-27%2C%0D%0A++++-4%5Cx+%2B+4%5Cy+=+8+%29%0D%0A++\"We'll use substitution. After moving -3*y to the right, we get:
\n" ); document.write( " \"-4%2Ax+=+-27+-+-3%2Ay\", or \"x+=+-27%2F-4+-+-3%2Ay%2F-4\". Substitute that
\n" ); document.write( " into another equation:
\n" ); document.write( " \"-4%2A%28-27%2F-4+-+-3%2Ay%2F-4%29+%2B+4%5Cy+=+8\" and simplify: So, we know that y=5. Since \"x+=+-27%2F-4+-+-3%2Ay%2F-4\", x=3.
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\n" ); document.write( " Answer: \"system%28+x=3%2C+y=5+%29\".
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\n" ); document.write( "\n" ); document.write( "Same result as before.\r
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\n" ); document.write( "\n" ); document.write( "I hope the above steps were helpful. \r
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\n" ); document.write( "\n" ); document.write( "For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.\r
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\n" ); document.write( "\n" ); document.write( "And good luck in your studies!\r
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\n" ); document.write( "\n" ); document.write( "Respectfully,
\n" ); document.write( "Dr J\r
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