Instead of doing yours for you, I'll do one exactly
like it, so you can use it as a model and learn to
do this kind of problem by yourself:
x+y+z = 6
2x-y+z = 3
x+2y-3z = -4
First put in all the 1, -1, and 0 coefficients, if
necessary:
Cramer's rule:
There are 4 columns,
1. The column of x-coefficients
2. The column of y-coefficients
3. The column of z-coefficients
4. The column of constants:
I colored the column of constants red because that is
the column that "moves" from left to right in the
determinants.
There are four determinants:
1. The determinant
consists of just the three columns
of x, y, and z coefficients. in that order, but does not
contain the column of constants.
.
It has value
. I'm assuming you know how to find the
value of a 3x3 determinant, for that's a subject all by itself.
If you don't know how, ask me in the thank-you note form below
this problem. I don't charge any money. I do this for fun!
2. The determinant
is like the determinant
except that the column of x-coefficients is replaced by the
column of constants.
does not contain the column
of x-coefficients.
.
It has value
.
3. The determinant
is like the determinant
except that the column of y-coefficients is replaced by the
column of constants.
does not contain the column
of y-coefficients.
.
It has value
.
4. The determinant
is like the determinant
except that the column of z-coefficients is replaced by the
column of constants.
does not contain the column
of z-coefficients.
.
It has value
.
Now the formulas for x, y and z are
Now do the same with yours.
[Hint as a check: Two of the values of your solution are
the same as two of the values in the problem I worked above.]
Edwin