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X - 2y + z = 4 x + y +z=2 3x + 3y + 3z = 14elimination method

User Aayush Mahajan
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1 Answer

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6 votes

To use elimination method we are going to multiply the first equation by -4 as:

(x - 2y + z)(-4) = 4(-4)

-4x + 8y - 4z = -16

Then, we can sum the equations as:

- 4x + 8y - 4z = -16

x + y + z = 2

3x + 3y + 3z = 14

0 + 12y + 0 = 0

So, we get the equation 12y = 0. It means that y is equal to 0

12y = 0

y = 0

Then, if we replace y by 0 on the initial equations, we get:

x + z = 4

x + z = 2

Since the sum of two numbers can't be 4 and 2 at the same time, the system doesn't have a solution.

Answer: the system doesn't have a solution.

User Andrew Coates
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