4=0.4(3d+5)

Solution for 4=0.4(3d+5) equation:

Simplifying
4 = 0.4(3d + 5)

Reorder the terms:
4 = 0.4(5 + 3d)
4 = (5 * 0.4 + 3d * 0.4)
4 = (2 + 1.2d)

Solving
4 = 2 + 1.2d

Solving for variable 'd'.

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

Add '-1.2d' to each side of the equation.
4 + -1.2d = 2 + 1.2d + -1.2d

Combine like terms: 1.2d + -1.2d = 0.0
4 + -1.2d = 2 + 0.0
4 + -1.2d = 2

Add '-4' to each side of the equation.
4 + -4 + -1.2d = 2 + -4

Combine like terms: 4 + -4 = 0
0 + -1.2d = 2 + -4
-1.2d = 2 + -4

Combine like terms: 2 + -4 = -2
-1.2d = -2

Divide each side by '-1.2'.
d = 1.666666667

Simplifying
d = 1.666666667