Question

X + 2y + 3z = 9 x - y - z = - 1 2x + y - 2z = 4

Answer 1

The values for the given equations are x=2,y=2 and z=1

Explanation:

Given equations are
`x+2y+3z=9\hfill (1)`

`x-y-z=-1\hfill (2)`

`2x+y-2z=4\hfill (3)`

Now solving the given equations

Subtracting equations (1) and (2) we get

`x+2y+3z=9`

`x-y-z=-1`

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`3y+4z=10\hfill (4)`

Multiplying the equation (2) into 2 we get

`2x-2y-2z=-2\hfill (5)`

Now subtracting equations (5) and (3) we get

`2x-2y-2z=-2`

`2x+y-2z=4`

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-3y=-6

`y=(6)/(3)`

Therefore y=2

Substitute y=2 in equation (4) we get

3y+4z=10

3(2)+4z=10

4z=10-6

`z=(4)/(4)`

Therefore z=1

Substitute y=2 and z=1 in equation (1) we get

x+2(2)+3(1)=9

x=9-3-4

Therefore x=2

Therefore the values for the given equations are x=2,y=2 and z=1