# How do you solve the system #x-4y-z=-3#, #x+2y+z=5#, and #3x-7y-2z=-6#?

##### 2 Answers

#### Explanation:

Add first two expressions to eliminate

the z

Multiply the first expression by -2, then add to the third expression to eliminate the z again

Multiply this answer by 2, then add to the first result to eliminate the y.

Substitute the x-value into one of the result formulae and solve for y

Substitute the x-value and the y-value into one of the original formulae and solve for z

Substitute your answers into BOTH of the other original formulae to check your results

#### Explanation:

Perform the Gauss Jordan elimination on the augmented matrix

I have written the equations not in the sequence as in the question in order to get

Perform the folowing operations on the rows of the matrix

Thus,