SOLUTION: how do we solve the below system using crammers rule? w+x+y+z=2 w+2x+3y+4z=2 2w+3x+5y+9z=2 w+x+2y+7z=2

Algebra ->  Matrices-and-determiminant -> SOLUTION: how do we solve the below system using crammers rule? w+x+y+z=2 w+2x+3y+4z=2 2w+3x+5y+9z=2 w+x+2y+7z=2      Log On


   



Question 874961: how do we solve the below system using crammers rule?
w+x+y+z=2
w+2x+3y+4z=2
2w+3x+5y+9z=2
w+x+2y+7z=2

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
1w+1x+1y+1z=2
1w+2x+3y+4z=2
2w+3x+5y+9z=2
1w+1x+2y+7z=2
first get the determinant of
{1,1,1,1
{1,2,3,4}
{2,3,5,9}
{1,1,2,7}
which is D=2
then get the determinant of
Dw =-6 from below
2,1,1,1
2,2,3,4
2,3,5,9
2,1,2,7
Dx=16
1,2,1,1
1,2,3,4
2,2,5,9
1,2,2,7
Dy=-10
1,1,2,1
1,2,2,4
2,3,2,9
1,1,2,7
Dz=2
1,1,1,2
1,2,3,2
2,3,5,2
1,1,2,2
w=Dw/D=-6/2=-3
x=Dx/D=16/2=8
y=Dy/D=-10/2=-5
z=Dz/D=2/2=1
and there you have it.