l+(l+1)+(l+2)+(l+3)=30

Solution for l+(l+1)+(l+2)+(l+3)=30 equation:

Simplifying
l + (l + 1) + (l + 2) + (l + 3) = 30

Reorder the terms:
l + (1 + l) + (l + 2) + (l + 3) = 30

Remove parenthesis around (1 + l)
l + 1 + l + (l + 2) + (l + 3) = 30

Reorder the terms:
l + 1 + l + (2 + l) + (l + 3) = 30

Remove parenthesis around (2 + l)
l + 1 + l + 2 + l + (l + 3) = 30

Reorder the terms:
l + 1 + l + 2 + l + (3 + l) = 30

Remove parenthesis around (3 + l)
l + 1 + l + 2 + l + 3 + l = 30

Reorder the terms:
1 + 2 + 3 + l + l + l + l = 30

Combine like terms: 1 + 2 = 3
3 + 3 + l + l + l + l = 30

Combine like terms: 3 + 3 = 6
6 + l + l + l + l = 30

Combine like terms: l + l = 2l
6 + 2l + l + l = 30

Combine like terms: 2l + l = 3l
6 + 3l + l = 30

Combine like terms: 3l + l = 4l
6 + 4l = 30

Solving
6 + 4l = 30

Solving for variable 'l'.

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

Add '-6' to each side of the equation.
6 + -6 + 4l = 30 + -6

Combine like terms: 6 + -6 = 0
0 + 4l = 30 + -6
4l = 30 + -6

Combine like terms: 30 + -6 = 24
4l = 24

Divide each side by '4'.
l = 6

Simplifying
l = 6