u=4(3n+30)+9(n+1)

Solution for u=4(3n+30)+9(n+1) equation:

Simplifying
u = 4(3n + 30) + 9(n + 1)

Reorder the terms:
u = 4(30 + 3n) + 9(n + 1)
u = (30 * 4 + 3n * 4) + 9(n + 1)
u = (120 + 12n) + 9(n + 1)

Reorder the terms:
u = 120 + 12n + 9(1 + n)
u = 120 + 12n + (1 * 9 + n * 9)
u = 120 + 12n + (9 + 9n)

Reorder the terms:
u = 120 + 9 + 12n + 9n

Combine like terms: 120 + 9 = 129
u = 129 + 12n + 9n

Combine like terms: 12n + 9n = 21n
u = 129 + 21n

Solving
u = 129 + 21n

Solving for variable 'u'.

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

Simplifying
u = 129 + 21n