Question 394042
ahhh I LOVE MATRICES :D

so just make your equation into a matrix first

[ 1  -2   4]   [x]       [-8]
| 2   2  -1|   |y|   =   |11|
[ 1   1  -2]   [z]       [10]

Let ^ = A              Let ^ = B

you CANT divide matrices, so multiply by the inverse, same thing right? :D

find the inverse of matrix A first, you can simply do this with a calculator
A^-1 * B 

And you'll find your answers will be

x = 4
y = 0
z = -3