document.write( "Question 1055331: Find the value(s)of b for which Z = \r
\n" ); document.write( "\n" ); document.write( "6 −b −4
\n" ); document.write( "b 0 1
\n" ); document.write( "1 −2 1\r
\n" ); document.write( "\n" ); document.write( " is singular\r
\n" ); document.write( "\n" ); document.write( "i worked it but not sure of the answer,
\n" ); document.write( "please show me the steps to get the answer.
\n" ); document.write( "thank you \n" ); document.write( "
Algebra.Com's Answer #670555 by Boreal(15235)\"\" \"About 
You can put this solution on YOUR website!
6===-b==-4== 6==-b
\n" ); document.write( "b====0==1===b===0
\n" ); document.write( "1===-2===1====1===-2
\n" ); document.write( "Need the determinant to be 0. I added the first and second columns to the right side, since sometimes that makes it easier to find the determinant.
\n" ); document.write( "8b-b-(-12-b^2)=0. Watch the signs here. We go left to right with 6*0*1=0 + b*-2*-4=8b+1*-b*1=-b. That is 7b. Then we subtract the quantity 1*0*4+-2*1*6+-1*b*-b=-12-b^2. That is adding 12+b^2. Then we have the quadratic equation below
\n" ); document.write( "7b+12+b^2=0
\n" ); document.write( "b^2+7b+12=0
\n" ); document.write( "(b+4)(b+3)=0
\n" ); document.write( "b=-4,-3
\n" ); document.write( "The matrix is
\n" ); document.write( "6===4===-4
\n" ); document.write( "-4==0====1
\n" ); document.write( "1===-2===1, and that determinant is 28-28
\n" ); document.write( "and
\n" ); document.write( "6===3===-4
\n" ); document.write( "-3===0===1
\n" ); document.write( "1===-2===1, and that determinant is -21-(-21)\r
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