an=n+(n+1)+(n+2)+(3n)

Solution for an=n+(n+1)+(n+2)+(3n) equation:

Simplifying
an = n + (n + 1) + (n + 2) + (3n)

Reorder the terms:
an = n + (1 + n) + (n + 2) + (3n)

Remove parenthesis around (1 + n)
an = n + 1 + n + (n + 2) + (3n)

Reorder the terms:
an = n + 1 + n + (2 + n) + (3n)

Remove parenthesis around (2 + n)
an = n + 1 + n + 2 + n + (3n)

Reorder the terms:
an = 1 + 2 + n + n + n + (3n)

Combine like terms: 1 + 2 = 3
an = 3 + n + n + n + (3n)

Combine like terms: n + n = 2n
an = 3 + 2n + n + (3n)

Combine like terms: 2n + n = 3n
an = 3 + 3n + (3n)

Combine like terms: 3n + (3n) = 6n
an = 3 + 6n

Solving
an = 3 + 6n

Solving for variable 'a'.

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

Divide each side by 'n'.
a = 3n-1 + 6

Simplifying
a = 3n-1 + 6

Reorder the terms:
a = 6 + 3n-1