Answer:
The measure of angle HBC is m∠HBC=61°
Step-by-step explanation:
In this problem we have that
The line BH bisects angle EBC,
see the attached figure to better understand the problem
then
m∠EBC=m∠EBH+m∠HBC
m∠EBH=m∠HBC
so
m∠EBC=2(m∠EBH)
substitute the given values and solve for a
[tex]31a-2=2(4a+45)\\31a-2=8a+90\\31a-8a=92\\23a=92\\a=4[/tex]
Find the measure of angle EBH
m∠EBH=(4(4)+45)=61°
Remember that
m∠EBH=m∠HBC
therefore
The measure of angle HBC is m∠HBC=61°