f=(f+12)+(f+60)

Solution for f=(f+12)+(f+60) equation:

Simplifying
f = (f + 12) + (f + 60)

Reorder the terms:
f = (12 + f) + (f + 60)

Remove parenthesis around (12 + f)
f = 12 + f + (f + 60)

Reorder the terms:
f = 12 + f + (60 + f)

Remove parenthesis around (60 + f)
f = 12 + f + 60 + f

Reorder the terms:
f = 12 + 60 + f + f

Combine like terms: 12 + 60 = 72
f = 72 + f + f

Combine like terms: f + f = 2f
f = 72 + 2f

Solving
f = 72 + 2f

Solving for variable 'f'.

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

Add '-2f' to each side of the equation.
f + -2f = 72 + 2f + -2f

Combine like terms: f + -2f = -1f
-1f = 72 + 2f + -2f

Combine like terms: 2f + -2f = 0
-1f = 72 + 0
-1f = 72

Divide each side by '-1'.
f = -72

Simplifying
f = -72