Spelling "Yeah" and "Yea"
Solution 1:
They are differentiated by spelling:
- Yay [ jɛi ] (as opposed to, say, boo) is for joy and exultation;
- Yeah [ jæ ] (synonym of yes, opposite of nah) is for ordinary assent; and
- Yea [ jɛi ] (opposite of nay) is for formal assent during a vote.
It's just that many people type yea (or even just ya) when they mean yeah.
Outside of the U.S., yeh [ jɛ ] is also common.