(X-3)-(x-3)=0

Solution for (X-3)-(x-3)=0 equation:

Simplifying
(X + -3) + -1(x + -3) = 0

Reorder the terms:
(-3 + X) + -1(x + -3) = 0

Remove parenthesis around (-3 + X)
-3 + X + -1(x + -3) = 0

Reorder the terms:
-3 + X + -1(-3 + x) = 0
-3 + X + (-3 * -1 + x * -1) = 0
-3 + X + (3 + -1x) = 0

Reorder the terms:
-3 + 3 + X + -1x = 0

Combine like terms: -3 + 3 = 0
0 + X + -1x = 0
X + -1x = 0

Solving
X + -1x = 0

Solving for variable 'X'.

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

Add 'x' to each side of the equation.
X + -1x + x = 0 + x

Combine like terms: -1x + x = 0
X + 0 = 0 + x
X = 0 + x
Remove the zero:
X = x

Simplifying
X = x