document.write( "Question 78377: I am not sure if this is solved by substitution, or elimination\r
\n" ); document.write( "\n" ); document.write( "4x - 6y = -14
\n" ); document.write( "x + 4y = 13 \n" ); document.write( "
Algebra.Com's Answer #56200 by dolly(163)\"\" \"About 
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Solution by substitution:\r
\n" ); document.write( "\n" ); document.write( "x + 4y = 13
\n" ); document.write( "==> x = 13 -4y ------------------(i)
\n" ); document.write( "Plugging in this value of x in the first equation, we get,
\n" ); document.write( "4(13-4y) - 6y = -14
\n" ); document.write( "==> 52 - 16y - 6y = -14
\n" ); document.write( "==> 52 - 22y = -14
\n" ); document.write( "adding -52 to both sides,
\n" ); document.write( "-22y = -14 -52
\n" ); document.write( "==> -22y = -66
\n" ); document.write( "==> -22y/22 = -66/22
\n" ); document.write( "==> y = 3
\n" ); document.write( "Putting this value in (i), x = 13 -4(3)
\n" ); document.write( " = 13 - 12
\n" ); document.write( " = 1\r
\n" ); document.write( "\n" ); document.write( "Thus x = 1 and y = 3\r
\n" ); document.write( "\n" ); document.write( "Solution by elimination:\r
\n" ); document.write( "\n" ); document.write( "4x - 6y = -14----------------------(1)
\n" ); document.write( "x + 4y = 13 ----------------------(2)\r
\n" ); document.write( "\n" ); document.write( "==> 4x + 16y = 52 -----------(2) x 4
\n" ); document.write( " 4x - 6y = - 14 -------------(1)
\n" ); document.write( "Subtracting the two equations we get,\r
\n" ); document.write( "\n" ); document.write( "16y + 6y = 52 + 14
\n" ); document.write( "==> 22y = 66
\n" ); document.write( "==> 22y/22= 66/22
\n" ); document.write( "==> y = 3
\n" ); document.write( "Plugging in this in (2), x = 13 - 4y\r
\n" ); document.write( "\n" ); document.write( " = 13 - 4(3)
\n" ); document.write( " = 13 - 12
\n" ); document.write( " = 1\r
\n" ); document.write( "\n" ); document.write( "Thus x = 1, y = 3
\n" ); document.write( " \n" ); document.write( "
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