expression
take care of it; I'll leave it up to you; do as you see fit
A set phrase used when entrusting a matter to someone else, implying 'handle it as you think best'. Often used in formal or slightly old-fashioned contexts.
See also: 計らう
この件はよきに計らえ。
Please handle this matter as you see fit.
後のことはよきに計らえと彼に任せた。
I left the rest to him, saying 'do as you see fit'.
The verb 計らう means 'to arrange' or 'to manage'; よきに計らえ is an imperative phrase derived from it, literally 'arrange it well'.
Derived from the classical adjective 良し (よし, 'good') in its adverbial form 良く (よく) with the archaic attributive き, plus the particle に and the imperative form of 計らう (はからう, 'to arrange'). The phrase literally means 'arrange it well'.