T5.6 3 of 6

So, one might well proceed as follows.

Premise 1. [A=(B=L)]&[C=(X&(B>L))]
Premise 2.  A
1 &E 3.  A=(B=L)
2,3 =E 4.  B=L
4 EQ 5. (B>L)&(L>B)
5 &E 6.  B>L

So, we are done pretty easily.

There are a few rules of strategy that work well in most cases.