Question
Use Cramer's Rule to solve each system of equations. a+b+5c=2
3a+b+2c=3
4a+2b-c=-3
3a+b+2c=3
4a+2b-c=-3
Answers
Steve
D =
|1 1 5|
|3 1 2|
|4 2 -1| = 16
Dx =
|2 1 5|
|3 1 2|
|-3 2 -1| = 32
Dy =
|1 2 5|
|3 3 2|
|4 -3 -1| = -80
Dz =
|1 1 2|
|3 1 3|
|4 2 -3| = 16
So, the solution
(x,y,z) = (Dx/D, Dy/D, Dz/D) = (2,-5,1)
|1 1 5|
|3 1 2|
|4 2 -1| = 16
Dx =
|2 1 5|
|3 1 2|
|-3 2 -1| = 32
Dy =
|1 2 5|
|3 3 2|
|4 -3 -1| = -80
Dz =
|1 1 2|
|3 1 3|
|4 2 -3| = 16
So, the solution
(x,y,z) = (Dx/D, Dy/D, Dz/D) = (2,-5,1)