Answer:
[tex]m<CBA=102\°[/tex]
Step-by-step explanation:
we know that
The internal angle of an equilateral triangle is equal to [tex]60\°[/tex]
The internal angle of a square is equal to [tex]90\°[/tex]
To find the internal angle of a regular pentagon, apply the formula
[tex]S=[(n-2)180\°]/n[/tex]
where
n is the number of sides (n=5)
substitute
[tex]S=[(5-2)180\°]/5=108\°[/tex]
therefore
In this problem
[tex]m<CBA+60\°+90\°+108\°=360\°[/tex]
[tex]m<CBA+258\°=360\°[/tex]
[tex]m<CBA=360\°-258\°=102\°[/tex]
