Answer:

given AB and CD are Interesting line at o

Step-by-step explanation:

aob is a line and od is a Ray so,angle aod + angle bod = 180degree ( linear pair) also ab and cd intersecting line so angle aod= angle cob ( vertically opposite angle) and angle aoc = angle bod (vertically opposite angle) let angle aod (x) so angle cob = x

angle aod is 90