3(1+6r)+6(r+3)=-51

Solution for 3(1+6r)+6(r+3)=-51 equation:

Simplifying
3(1 + 6r) + 6(r + 3) = -51
(1 * 3 + 6r * 3) + 6(r + 3) = -51
(3 + 18r) + 6(r + 3) = -51

Reorder the terms:
3 + 18r + 6(3 + r) = -51
3 + 18r + (3 * 6 + r * 6) = -51
3 + 18r + (18 + 6r) = -51

Reorder the terms:
3 + 18 + 18r + 6r = -51

Combine like terms: 3 + 18 = 21
21 + 18r + 6r = -51

Combine like terms: 18r + 6r = 24r
21 + 24r = -51

Solving
21 + 24r = -51

Solving for variable 'r'.

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

Add '-21' to each side of the equation.
21 + -21 + 24r = -51 + -21

Combine like terms: 21 + -21 = 0
0 + 24r = -51 + -21
24r = -51 + -21

Combine like terms: -51 + -21 = -72
24r = -72

Divide each side by '24'.
r = -3

Simplifying
r = -3