0.1(x+20)+0.1x=3

Solution for 0.1(x+20)+0.1x=3 equation:

Simplifying
0.1(x + 20) + 0.1x = 3

Reorder the terms:
0.1(20 + x) + 0.1x = 3
(20 * 0.1 + x * 0.1) + 0.1x = 3
(2 + 0.1x) + 0.1x = 3

Combine like terms: 0.1x + 0.1x = 0.2x
2 + 0.2x = 3

Solving
2 + 0.2x = 3

Solving for variable 'x'.

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

Add '-2' to each side of the equation.
2 + -2 + 0.2x = 3 + -2

Combine like terms: 2 + -2 = 0
0 + 0.2x = 3 + -2
0.2x = 3 + -2

Combine like terms: 3 + -2 = 1
0.2x = 1

Divide each side by '0.2'.
x = 5

Simplifying
x = 5