.4(r-2)=.15(r-4)

Solution for .4(r-2)=.15(r-4) equation:

Simplifying
0.4(r + -2) = 0.15(r + -4)

Reorder the terms:
0.4(-2 + r) = 0.15(r + -4)
(-2 * 0.4 + r * 0.4) = 0.15(r + -4)
(-0.8 + 0.4r) = 0.15(r + -4)

Reorder the terms:
-0.8 + 0.4r = 0.15(-4 + r)
-0.8 + 0.4r = (-4 * 0.15 + r * 0.15)
-0.8 + 0.4r = (-0.6 + 0.15r)

Solving
-0.8 + 0.4r = -0.6 + 0.15r

Solving for variable 'r'.

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

Add '-0.15r' to each side of the equation.
-0.8 + 0.4r + -0.15r = -0.6 + 0.15r + -0.15r

Combine like terms: 0.4r + -0.15r = 0.25r
-0.8 + 0.25r = -0.6 + 0.15r + -0.15r

Combine like terms: 0.15r + -0.15r = 0.00
-0.8 + 0.25r = -0.6 + 0.00
-0.8 + 0.25r = -0.6

Add '0.8' to each side of the equation.
-0.8 + 0.8 + 0.25r = -0.6 + 0.8

Combine like terms: -0.8 + 0.8 = 0.0
0.0 + 0.25r = -0.6 + 0.8
0.25r = -0.6 + 0.8

Combine like terms: -0.6 + 0.8 = 0.2
0.25r = 0.2

Divide each side by '0.25'.
r = 0.8

Simplifying
r = 0.8