- #1
Schaus
- 118
- 5
Homework Statement
Determine the values of a for which the following system of linear equations has no solutions, a unique solution, or infinitely many solutions. You can select 'always', 'never', 'a = ', or 'a ≠', then specify a value or comma-separated list of values.
x1−2x2+2x3 = −1
−3x1+ax2−10x3 = 5
x1+x2−4x3 = 3
Homework Equations
Augmented Matrix
The Attempt at a Solution
1 -2 2 -1
-3 a -10 5
1 1 -4 3
I switched the row with the variable to the bottom.
1 -2 2 -1
1 1 -4 3
-3 a -10 5
I minused Row 1 from Row 2
1 -2 2 -1
0 3 -6 5
-3 a -10 5
3Row 1 + Row 3
1 -2 2 -1
0 3 -6 5
0 (a-6) -4 2
Here is where I get confused. I don't know how to get the 3 in row 2 to equal 1 and get the (a-6) to equal 0.
Any advice as to where I went wrong or what I need to do next would be greatly appreciated!