document.write( "Question 1184020: Given the following systems of equations
\n" ); document.write( "2x + y+ z = 12
\n" ); document.write( "6x + 5 y - 3z = 6
\n" ); document.write( "4x - y + 3z = 5
\n" ); document.write( "Solve for the x,y and z using:
\n" ); document.write( "(i) Gaussian elimination
\n" ); document.write( "(ii) Gauss- Jordan elimination
\n" ); document.write( "(iii) Use Sarrus` rule to find determinant of the equation above
\n" ); document.write( "(iv) Cramer`s rule
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Algebra.Com's Answer #814559 by MathLover1(20850)\"\" \"About 
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Given the following systems of equations\r
\n" ); document.write( "\n" ); document.write( "\"2x+%2B+y%2B+z+=+12\"
\n" ); document.write( "\"6x+%2B+5+y+-+3z+=+6\"
\n" ); document.write( "\"4x+-+y+%2B+3z+=+5\"\r
\n" ); document.write( "\n" ); document.write( "Solve for the \"x\",\"y+\"and \"z\" using:\r
\n" ); document.write( "\n" ); document.write( "(i) Gaussian elimination\r
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\n" ); document.write( "\n" ); document.write( "R1 / 2 → R1 (divide the 1 row by 2)\r
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\n" ); document.write( "\n" ); document.write( "R2 - 6 R1 → R2 (multiply 1 row by 6 and subtract it from 2 row); R3 - 4 R1 → R3 (multiply 1 row by 4 and subtract it from 3 row)\r
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\n" ); document.write( "\n" ); document.write( "R2 / 2 → R2 (divide the 2 row by 2)\r
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\n" ); document.write( "\n" ); document.write( "R1 - 0.5 R2 → R1 (multiply 2 row by 0.5 and subtract it from 1 row); R3 + 3 R2 → R3 (multiply 2 row by 3 and add it to 3 row)\r
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\n" ); document.write( "\n" ); document.write( "R3 / -8 → R3 (divide the 3 row by -8)\r
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\n" ); document.write( "\n" ); document.write( "R1 - 2 R3 → R1 (multiply 3 row by 2 and subtract it from 1 row); R2 + 3 R3 → R2 (multiply 3 row by 3 and add it to 2 row)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+-2.5\"
\n" ); document.write( "\"y+=+9\"
\n" ); document.write( "\"z+=+8\"\r
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\n" ); document.write( "\n" ); document.write( "(ii) Gauss- Jordan elimination\r
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\n" ); document.write( "\n" ); document.write( "Make the pivot in the 1st column by dividing the 1st row by 2\r
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\n" ); document.write( "\n" ); document.write( "Eliminate the 1st column\r
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\n" ); document.write( "\n" ); document.write( "Make the pivot in the 2nd column by dividing the 2nd row by 2\r
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\n" ); document.write( "\n" ); document.write( "Eliminate the 2nd column\r
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\n" ); document.write( "\n" ); document.write( "Make the pivot in the 3rd column by dividing the 3rd row by -8\r
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\n" ); document.write( "\n" ); document.write( "Eliminate the 3rd column\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+-2.5\"
\n" ); document.write( "\"y+=+9\"
\n" ); document.write( "\"z+=+8\"\r
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\n" ); document.write( "\n" ); document.write( "(iv) Cramer`s rule\r
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\n" ); document.write( "\n" ); document.write( "Write down the main matrix and find its determinant\r
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\n" ); document.write( "\n" ); document.write( "Δ =
\n" ); document.write( "Δ =\"30-6-12+-6-18-20\"
\n" ); document.write( "Δ =\"-32\"\r
\n" ); document.write( "\n" ); document.write( "Replace the 1st column of the main matrix with the solution vector and find its determinant\r
\n" ); document.write( "\n" ); document.write( "\"matrix%283%2C3%2C12%2C%091%2C%091%2C%0D%0A6%2C%095%2C%09-3%2C%0D%0A5%2C%09-1%2C%093%29\"\r
\n" ); document.write( "\n" ); document.write( "Δ1 = \"80\"\r
\n" ); document.write( "\n" ); document.write( "Replace the 2nd column of the main matrix with the solution vector and find its determinant\r
\n" ); document.write( "\n" ); document.write( "\"matrix%283%2C3%2C2%2C%0912%2C%091%2C%0D%0A6%2C%096%2C%09-3%2C%0D%0A4%2C%095%2C%093%29\"\r
\n" ); document.write( "\n" ); document.write( "Δ2 =\"+-288\"\r
\n" ); document.write( "\n" ); document.write( "Replace the 3rd column of the main matrix with the solution vector and find its determinant\r
\n" ); document.write( "\n" ); document.write( "\"matrix%283%2C3%2C2%2C%091%2C%0912%2C%0D%0A6%2C%095%2C%096%2C%0D%0A4%2C%09-1%2C%095%29\"\r
\n" ); document.write( "\n" ); document.write( "Δ3 = \"-256\"\r
\n" ); document.write( "\n" ); document.write( "\"x+\"= Δ1 / Δ = \"80+%2F+%28-32%29+=+-5%2F2\"
\n" ); document.write( "\"y+\"= Δ2 / Δ = \"%28-288%29+%2F+%28-32%29+=+9\"
\n" ); document.write( "\"z\" = Δ3 / Δ =\"+%28-256%29+%2F+%28-32%29+=+8\"\r
\n" ); document.write( "\n" ); document.write( "leaving to you to do:\r
\n" ); document.write( "\n" ); document.write( "(iii) Use Sarrus` rule to find determinant of the equation above\r
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