0.9x-0.9(4-x)=0.9

Solution for 0.9x-0.9(4-x)=0.9 equation:

Simplifying
0.9x + -0.9(4 + -1x) = 0.9
0.9x + (4 * -0.9 + -1x * -0.9) = 0.9
0.9x + (-3.6 + 0.9x) = 0.9

Reorder the terms:
-3.6 + 0.9x + 0.9x = 0.9

Combine like terms: 0.9x + 0.9x = 1.8x
-3.6 + 1.8x = 0.9

Solving
-3.6 + 1.8x = 0.9

Solving for variable 'x'.

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

Add '3.6' to each side of the equation.
-3.6 + 3.6 + 1.8x = 0.9 + 3.6

Combine like terms: -3.6 + 3.6 = 0.0
0.0 + 1.8x = 0.9 + 3.6
1.8x = 0.9 + 3.6

Combine like terms: 0.9 + 3.6 = 4.5
1.8x = 4.5

Divide each side by '1.8'.
x = 2.5

Simplifying
x = 2.5