Answer:
SAS postulate
Step-by-step explanation:
AD (common)
AC = BD (both are diameters)
Angle COD = Ange AOD (vertically opposite angles)
Angle CAD = Angle BAD (angle on the circumference is half the angle at the centre)
Therefore, ABD and DCA are congruent by SAS postulate
The answer for this is X+2g= 0
21 degrees C ????????????