Am I Correct in assuming this?

dH of solution = -dH of lattice enthalpy + dH of hydration

E.g:
dHsolution NaCl = -dHLE NaCl(s) + dHhyd Na+(g) + dHhyd Cl-(g)

Units as kJmol-1

2 answers

Your signs on the right side are reversed. Bond breaking is endothermic and bond formation is exothermic. Some bond formations are endothermic (i.e. hydrogen bonding) that must be taken into account in conjunction with hydration which is also bond formation.
∆H(soln) = |∆H(lattice)| - ∆H(solute-solvent)
How is this Possible GK.
Everywhere I have looked, including mark schemes and chemistry websites dH(solution) is worked out via this equation:

dH(solution) = dH(LE) - dH(hyd) + dH(hyd)

What is it you are working out with solute and solvent?