12=-2r+1-1

Solution for 12=-2r+1-1 equation:

Simplifying
12 = -2r + 1 + -1

Reorder the terms:
12 = 1 + -1 + -2r

Combine like terms: 1 + -1 = 0
12 = 0 + -2r
12 = -2r

Solving
12 = -2r

Solving for variable 'r'.

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

Add '2r' to each side of the equation.
12 + 2r = -2r + 2r

Combine like terms: -2r + 2r = 0
12 + 2r = 0

Add '-12' to each side of the equation.
12 + -12 + 2r = 0 + -12

Combine like terms: 12 + -12 = 0
0 + 2r = 0 + -12
2r = 0 + -12

Combine like terms: 0 + -12 = -12
2r = -12

Divide each side by '2'.
r = -6

Simplifying
r = -6