To answer this, you will need to know a property about parallelograms.
The property states: The diagonals of a parallelogram bisect each other.
Bisect: To split into 2 equivalent parts.
We'll put that to the side for now, it will come handy later into this explanation.
We know that...
\(LW = LJ - WJ\)
\(5x + 2 = 11x + 2 - WJ\)
So, what's WJ?
Let's refer back to what we said earlier.
The diagonals of a parallelogram bisect each other.
Now we know that \(LW = WJ\).
We can change our equation to make it solvable.
\(5x + 2 = 11x + 2 - (5x + 2)\)
\(5x + 2 = 11x + 2 - 5x - 2\)
\(5x+2=6x\)
\(x=2\)
Now substitute the value of x into 5x+2.
\(5x+2=5(2)+2\)
\(5x+2=12\)
\(LW = 12\)
And you are done!
