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5 votes
X + 2y=-6
y = 2z =2
-2x- 6y + 5z =26

User Flowtron
by
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1 Answer

3 votes

To eliminate y from the first equation, we can multiply the entire equation by -2. This will give us:

-2x - 4y = -12

Now, if we add this equation to the second equation, the y terms will cancel out, leaving us with:

-2x - 4(2) + 5z = 26

-2x + 5z = 26

Now we have two equations in two variables, x and z. We can solve this system of equations by substituting the value of y from the second equation into the first equation. This gives us:

x + 2(2) = -6

x = -10

Substituting this value of x into the second equation, we get:

-2(-10) + 5z = 26

20 + 5z = 26

5z = 6

z = 1.2

Finally, we can substitute the values of x and z back into the second equation to find the value of y:

-2(-10) - 6(1.2) + 5(1.2) = 26

20 - 7.2 + 6 = 26

12.8 = 26

This system of equations has no solution, since we have found values of x and z that make the second equation true, but substituting these values into the first equation results in a false statement. This means that there is no set of values for x, y, and z that will make all three equations true at the same time.

User Valath
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4.1k points