2r+3(r+2)+4r=12

Solution for 2r+3(r+2)+4r=12 equation:

Simplifying
2r + 3(r + 2) + 4r = 12

Reorder the terms:
2r + 3(2 + r) + 4r = 12
2r + (2 * 3 + r * 3) + 4r = 12
2r + (6 + 3r) + 4r = 12

Reorder the terms:
6 + 2r + 3r + 4r = 12

Combine like terms: 2r + 3r = 5r
6 + 5r + 4r = 12

Combine like terms: 5r + 4r = 9r
6 + 9r = 12

Solving
6 + 9r = 12

Solving for variable 'r'.

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

Add '-6' to each side of the equation.
6 + -6 + 9r = 12 + -6

Combine like terms: 6 + -6 = 0
0 + 9r = 12 + -6
9r = 12 + -6

Combine like terms: 12 + -6 = 6
9r = 6

Divide each side by '9'.
r = 0.6666666667

Simplifying
r = 0.6666666667