document.write( "Question 176531: What is BA: B=[2, 8, .6, 3] A=[3, 0, 2, -1] \n" ); document.write( "
Algebra.Com's Answer #131628 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
I'm assuming that the matrices are:\r
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\n" ); document.write( "\n" ); document.write( "\"B=%28matrix%282%2C2%2C2%2C8%2C0.6%2C3%29%29\" and \"A=%28matrix%282%2C2%2C3%2C0%2C2%2C-1%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"BA\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"%28matrix%282%2C2%2C2%2C8%2C0.6%2C3%29%29%28matrix%282%2C2%2C3%2C0%2C2%2C-1%29%29\" Plug in \"B=%28matrix%282%2C2%2C2%2C8%2C0.6%2C3%29%29\" and \"A=%28matrix%282%2C2%2C3%2C0%2C2%2C-1%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Since the first matrix is a 2 by 2 matrix and the second matrix is a 2 by 2 matrix, this means that the resulting matrix will be a 2 by 2 matrix.\r
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\n" ); document.write( "\n" ); document.write( "So the final resulting matrix will look like:\r
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\n" ); document.write( "\n" ); document.write( "\"%28matrix%282%2C2%2Cx%2Cx%2Cx%2Cx%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "note: the \"x\"s are just placeholders for now\r
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\n" ); document.write( "\n" ); document.write( "Multiply the corresponding entries from the 1st row of the first matrix by the 1st column of the second matrix. After multiplying, add the values:\r
\n" ); document.write( "\n" ); document.write( "1st row, 1st column: \r
\n" ); document.write( "\n" ); document.write( "\"%282%29%2A%283%29%2B%288%29%2A%282%29=6%2B16=22\"\r
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\n" ); document.write( "\n" ); document.write( " So the element in the 1st row, 1st column of the resulting matrix is \"22\". Now let's update the matrix:\r
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\n" ); document.write( "\n" ); document.write( "\"%28matrix%282%2C2%2C22%2Cx%2Cx%2Cx%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Multiply the corresponding entries from the 1st row of the first matrix by the 2nd column of the second matrix. After multiplying, add the values:\r
\n" ); document.write( "\n" ); document.write( "1st row, 2nd column: \r
\n" ); document.write( "\n" ); document.write( "\"%282%29%2A%280%29%2B%288%29%2A%28-1%29=0%2B-8=-8\"\r
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\n" ); document.write( "\n" ); document.write( " So the element in the 1st row, 2nd column of the resulting matrix is \"-8\". Now let's update the matrix:\r
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\n" ); document.write( "\n" ); document.write( "\"%28matrix%282%2C2%2C22%2C-8%2Cx%2Cx%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Multiply the corresponding entries from the 2nd row of the first matrix by the 1st column of the second matrix. After multiplying, add the values:\r
\n" ); document.write( "\n" ); document.write( "2nd row, 1st column: \r
\n" ); document.write( "\n" ); document.write( "\"%280.6%29%2A%283%29%2B%283%29%2A%282%29=1.8%2B6=7.8\"\r
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\n" ); document.write( "\n" ); document.write( " So the element in the 2nd row, 1st column of the resulting matrix is \"7.8\". Now let's update the matrix:\r
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\n" ); document.write( "\n" ); document.write( "\"%28matrix%282%2C2%2C22%2C-8%2C7.8%2Cx%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Multiply the corresponding entries from the 2nd row of the first matrix by the 2nd column of the second matrix. After multiplying, add the values:\r
\n" ); document.write( "\n" ); document.write( "2nd row, 2nd column: \r
\n" ); document.write( "\n" ); document.write( "\"%280.6%29%2A%280%29%2B%283%29%2A%28-1%29=0%2B-3=-3\"\r
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\n" ); document.write( "\n" ); document.write( " So the element in the 2nd row, 2nd column of the resulting matrix is \"-3\". Now let's update the matrix:\r
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\n" ); document.write( "\n" ); document.write( "\"%28matrix%282%2C2%2C22%2C-8%2C7.8%2C-3%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the solution is \"%28matrix%282%2C2%2C22%2C-8%2C7.8%2C-3%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "In other words,\r
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\n" ); document.write( "\n" ); document.write( "So this means that \"BA=%28matrix%282%2C2%2C22%2C-8%2C7.8%2C-3%29%29\"
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