Answer
The chemical formula for the conjugate acid of $Br^-$ is:
$HBr$
Work Step by Step
To find the conjugate acid of a base, you just need to add a proton $(H^+)$ to the compound.
1. Add one hydrogen.
$Br^- --\gt HBr^-$
2. Add "+1" to the charge of the compound:
$-1 -- \gt 0$
$HBr^- --\gt HBr$
