A = B + C + 2neutrons
The equation is balanced i.e no of nucleons are the same on both sides of the equation.
To find the energy released using binding energy ignore the neutrons as they do not have binding energy as they are single neutrons .
Find energy needed to break up A, B and C into its constituents i.e nucleons
You will find that the energy to break up A is lower that the energy needed to break up B and C together , as B and C are more stable products than A.
Therefore in forming B and C from A there will be further release of energy. This energy can be calculated by BE(B) + BE(C) - BE (A)
