3. AgNO3 + HBr = 2. Ba(OH2) + H3PO4 =

Here are the balanced chemical equations for the reactions you provided:

1. Reaction of Silver Nitrate with Hydrobromic Acid: \[ \text{AgNO}_3 + \text{HBr} \rightarrow \text{AgBr} + \text{HNO}_3 \] In this reaction, silver bromide (AgBr) is formed as a precipitate, along with nitric acid (HNO₃).

2. Reaction of Barium Hydroxide with Phosphoric Acid: \[ \text{Ba(OH)}_2 + 2 \text{H}_3\text{PO}_4 \rightarrow \text{Ba}_3(\text{PO}_4)_2 + 6 \text{H}_2\text{O} \] This reaction produces barium phosphate (Ba₃(PO₄)₂) and water.

Please check for any required coefficients or states of matter based on your context or specific instructions.