SOLUTION: solve the linear system of equations by crammers rule= -1/2x+3y+2z=-1 +3x+4y+5z=-2 -6x+3y-2z=-7

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Question 1204264: solve the linear system of equations by crammers rule=
-1/2x+3y+2z=-1
+3x+4y+5z=-2
-6x+3y-2z=-7

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
 

To solve using Cramer's rule:
 
There are 4 columns,
 
1. The column of x-coefficients matrix%283%2C1%2C1%2F2%2C3%2C-6%29
 
2. The column of y-coefficients matrix%283%2C1%2C3%2C4%2C3%29
 
3. The column of z-coefficients matrix%283%2C1%2C2%2C5%2C-2%29 
 
4. The column of constants:     red%28matrix%283%2C1%2C-1%2C-2%2C-7%29%29
 
There are four determinants:
 
1. The determinant D consists of just the three columns
of x, y, and z coefficients. in that order, but does not
contain the column of constants.
 
D=abs%28matrix%283%2C3%2C-1%2F2%2C3%2C2%2C3%2C4%2C5%2C-6%2C3%2C-2%29%29. 
 
It has value D=5.5.  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, post again asking how. 
 
2. The determinant D%5Bx%5D is like the determinant D
except that the column of x-coefficients is replaced by the
column of constants.  D%5Bx%5D does not contain the column 
of x-coefficients.
 
.
 
It has value D%5Bx%5D=-50.
 
3. The determinant D%5By%5D is like the determinant D
except that the column of y-coefficients is replaced by the
column of constants.  D%5By%5D does not contain the column 
of y-coefficients.
 
.
 
It has value D%5By%5D=-61.5.
 
4. The determinant D%5Bz%5D is like the determinant D
except that the column of z-coefficients is replaced by the
column of constants.  D%5Bz%5D does not contain the column 
of z-coefficients.
 
.
 
It has value D%5Bz%5D=77.
 
Now the formulas for x, y and z are
 
x=D%5Bx%5D%2FD=%28-50%29%2F%285.5%29=-500%2F55=-100%2F11
y=D%5By%5D%2FD=%28-61.5%29%2F%285.5%29=-615%2F55=-123%2F11
x=D%5Bz%5D%2FD=%2877%29%2F%285.5%29=770%2F55=14

Answer: x=-100%2F11`  y=-123%2F11    z=14

Edwin