What is the measure of x?

Answer:
Step-by-step explanation:
[tex]m\angle BHD=180^o-x^o[/tex]
[tex]m\angle DBH+m\angle BHD+m\angle HDB=180^o\\\\47^o+180^o-x^o+31^o=180^o\\\\78^o-x^o=0\\\\x^o=78^o[/tex]