document.write( "Question 1050415: Hi, I'm having trouble with this question. I don't know how I'm supposed to work it out, so any help would be great appreciated! Thank you!
\n" ); document.write( "Determine the values for \"a\" for which the following system of linear equations has no solutions, a unique solution, or infinitely many solutions. I need to solve using a matrix, and then row reducing.
\n" ); document.write( "3X1 + aX2 + 6X3 = 6
\n" ); document.write( "-X1 + 3X2 - X3 = 1
\n" ); document.write( "2X1 - 2X2 + 6X3 = 11
\n" ); document.write( "

Algebra.Com's Answer #665970 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
Determine the values for \"a\" for which the following system of linear equations has no solutions, a unique solution, or infinitely many solutions. I need to solve using a matrix, and then row reducing.
\n" ); document.write( "3X1 + aX2 + 6X3 = 6
\n" ); document.write( "-X1 + 3X2 - X3 = 1
\n" ); document.write( "2X1 - 2X2 + 6X3 = 11
\n" ); document.write( "------------------------
\n" ); document.write( "You have to find the determinant of the \"coefficient matrix\"::
\n" ); document.write( "--------
\n" ); document.write( "D = (3*3*6 + (-1*2*6) + (2*-1*a) - [(6*3*2)+(-1*-2*3)+(6*-1*a))
\n" ); document.write( "----
\n" ); document.write( "D = (54 - 12 - 2a - [36 + 6 - 6a])
\n" ); document.write( "----
\n" ); document.write( "D = (42-2a)-(42-6a)
\n" ); document.write( "---
\n" ); document.write( "D = 4a
\n" ); document.write( "-----
\n" ); document.write( "One unique solution if a is not zero
\n" ); document.write( "No solution when a = 0
\n" ); document.write( "----
\n" ); document.write( "I'll leave the row reducing to you.
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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