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Solve the system by substitution
2x-y+z=-4
z=5
-2x+3y-z=10

1 Answer

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Final answer:

The system is solved by substitution by first inserting the given value of z into the other equations, simplifying, and solving for x and y sequentially. The final solution to the system of equations is x = -3, y = 3, and z = 5.

Step-by-step explanation:

To solve the system by substitution, we start by analyzing the given equations.

2x - y + z = -4

z = 5

-2x + 3y - z = 10

With the value of z given as 5, we substitute it into the first and third equations.

2x - y + 5 = -4

-2x + 3y - 5 = 10

After substitution, we simplify and solve for y in the first equation:

2x - y = -9

y = 2x + 9

Then, substitute y into the third equation:

-2x + 3(2x + 9) - 5 = 10

-2x + 6x + 27 - 5 = 10

4x + 22 = 10

4x = -12

x = -3

With x found, we substitute it back into the equation for y:

y = 2(-3) + 9

y = -6 + 9

y = 3

Now we have found that x = -3, y = 3, and z = 5.

User Zach Perry
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