Beau has a special form, bel, that is only used in front of a masculine singular noun that begins with a vowel or mute h: un bel homme, un beau garçon.

The plural of both is the same: beaux hommes, beaux garçons.

Learn more: https://progress.lawlessfrench.com/my-languages/french/view/113

Je vous en prie. :-)

But you've made a very similar mistake: "ta explanation".

For the same reason (to avoid hiatus) that we say bel homme rather than "beau homme", you have to say ton explication: https://progress.lawlessfrench.com/my-languages/french/view/132