x+y-z=k+m

Solution for x+y-z=k+m equation:

Simplifying
x + y + -1z = k + m

Solving
x + y + -1z = k + m

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-1y' to each side of the equation.
x + y + -1y + -1z = k + m + -1y

Combine like terms: y + -1y = 0
x + 0 + -1z = k + m + -1y
x + -1z = k + m + -1y

Add 'z' to each side of the equation.
x + -1z + z = k + m + -1y + z

Combine like terms: -1z + z = 0
x + 0 = k + m + -1y + z
x = k + m + -1y + z

Simplifying
x = k + m + -1y + z