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Each of the given linear systems is in row echelon form. Solve the system x + y - z + 2w = 4, w = 5.

User Kobato
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Final answer:

The linear system x + y - z + 2w = 4, w = 5 can be solved by substituting w = 5 into the first equation, resulting in x + y - z = -6. This system is underdetermined with infinitely many solutions. A particular solution can be given by setting two variables to arbitrary values and solving for the third.

Step-by-step explanation:

To solve the linear system given in row echelon form, we have the equations x + y - z + 2w = 4, and w = 5. Since we already know the value of w, we can substitute it directly into the first equation:

  • x + y - z + 2(5) = 4
  • x + y - z + 10 = 4
  • x + y - z = -6

Now we are left with a system of two equations and three unknowns (x, y, z). This is underdetermined, meaning there are an infinite number of solutions depending on the values chosen for x and y. To find particular solutions, you can set two of the variables to arbitrary values and solve for the third. For example, you could set x = 0 and solve for y and z, or set y = 0 and solve for x and z, and so on.

The final step involves expressing the solutions in terms of the free variable(s). For instance, if we set x = 0, then we would have:

  • 0 + y - z = -6
  • y - z = -6

In this case, we could express z in terms of y: z = y + 6.

Hence, the solution set can be described by two parameters, y and z, where z is dependent on y.

User Flipdoubt
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