0.4(m+4)=0.2(3m+9)

Solution for 0.4(m+4)=0.2(3m+9) equation:

Simplifying
0.4(m + 4) = 0.2(3m + 9)

Reorder the terms:
0.4(4 + m) = 0.2(3m + 9)
(4 * 0.4 + m * 0.4) = 0.2(3m + 9)
(1.6 + 0.4m) = 0.2(3m + 9)

Reorder the terms:
1.6 + 0.4m = 0.2(9 + 3m)
1.6 + 0.4m = (9 * 0.2 + 3m * 0.2)
1.6 + 0.4m = (1.8 + 0.6m)

Solving
1.6 + 0.4m = 1.8 + 0.6m

Solving for variable 'm'.

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

Add '-0.6m' to each side of the equation.
1.6 + 0.4m + -0.6m = 1.8 + 0.6m + -0.6m

Combine like terms: 0.4m + -0.6m = -0.2m
1.6 + -0.2m = 1.8 + 0.6m + -0.6m

Combine like terms: 0.6m + -0.6m = 0.0
1.6 + -0.2m = 1.8 + 0.0
1.6 + -0.2m = 1.8

Add '-1.6' to each side of the equation.
1.6 + -1.6 + -0.2m = 1.8 + -1.6

Combine like terms: 1.6 + -1.6 = 0.0
0.0 + -0.2m = 1.8 + -1.6
-0.2m = 1.8 + -1.6

Combine like terms: 1.8 + -1.6 = 0.2
-0.2m = 0.2

Divide each side by '-0.2'.
m = -1

Simplifying
m = -1