document.write( "Question 389348: find the value of the determinant. \r
\n" ); document.write( "\n" ); document.write( "1 4 7
\n" ); document.write( "-2 5 2
\n" ); document.write( "2 5 -2 \n" ); document.write( "

Algebra.Com's Answer #275881 by haileytucki(390) $\"\"$ $\"About$

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M[1,4,7:-2,5,2:2,5,-2]\r
\n" ); document.write( "\n" ); document.write( "Setup the determinant by breaking it into smaller components.
\n" ); document.write( "1M[D,5,2:5,-2]-(-2)M[D,4,7:5,-2]+2M[D,4,7:5,2]\r
\n" ); document.write( "\n" ); document.write( "The determinant of a 2x2 matrix can be found using the formula M[D,a,b:c,d]=ad-cb
\n" ); document.write( "(5)(-2)-(5)(2)-(-2)M[D,4,7:5,-2]+2M[D,4,7:5,2]\r
\n" ); document.write( "\n" ); document.write( "Simplify the determinant.
\n" ); document.write( "-20-(-2)M[D,4,7:5,-2]+2M[D,4,7:5,2]\r
\n" ); document.write( "\n" ); document.write( "The determinant of a 2x2 matrix can be found using the formula M[D,a,b:c,d]=ad-cb
\n" ); document.write( "-20-(-2)((4)(-2)-(5)(7))+2M[D,4,7:5,2]\r
\n" ); document.write( "\n" ); document.write( "Simplify the determinant.
\n" ); document.write( "-20-86+2M[D,4,7:5,2]\r
\n" ); document.write( "\n" ); document.write( "The determinant of a 2x2 matrix can be found using the formula M[D,a,b:c,d]=ad-cb
\n" ); document.write( "-20-86+2((4)(2)-(5)(7))\r
\n" ); document.write( "\n" ); document.write( "Simplify the determinant.
\n" ); document.write( "-20-86-54\r
\n" ); document.write( "\n" ); document.write( "Simplify the expression.
\n" ); document.write( "-160 \n" ); document.write( "

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