Answer:

Step-by-step explanation:
When a quadrilateral is inscribed in a circle, the opposite angles of it add up to 180 degrees.
Here,
∠DCB + ∠DAB = 180 (Opposite angles of a quad inscribed in a circle.)
<u>Given that:</u> ∠DCB = 135° and ∠DAB = x
135 + x = 180
Subtract 135 to both sides
x = 180 - 135
x = 55°
![\rule[225]{225}{2}](https://tex.z-dn.net/?f=%5Crule%5B225%5D%7B225%7D%7B2%7D)
Hope this helped!
<h3>~AH1807</h3>
Assuming you mean the central angle, semicircles have central angles of
.
Answer:
25.12
Step-by-step explanation:
The answer is D because if you add all the same terms you get the answer