Given:
A figure of a circle.
To find:
The value of x.
Solution:
First label the given figure as shown below.
In triangle ABO,
[tex]OA=OB[/tex] (Radii of same circle)
[tex]\Delta ABO[/tex] is an isosceles triangle. (By the definition of isosceles triangle)
[tex]\angle OAB\cong \angle OBA[/tex] (Base angles of an isosceles triangle)
[tex]m\angle OAB=m\angle OBA[/tex]
[tex]42^\circ=m\angle OBA[/tex]
In triangle ABO,
[tex]m\angle AOB+m\angle OAB+m\angle OBA=180^\circ[/tex] (Angle sum property)
[tex]m\angle AOB+42^\circ+42^\circ=180^\circ[/tex]
[tex]m\angle AOB=180^\circ-42^\circ-42^\circ[/tex]
[tex]m\angle AOB=96^\circ[/tex]
Now,
[tex]m\angle AOB+m\angle BOC=180^\circ[/tex] (Linear pair)
[tex]96^\circ+x=180^\circ[/tex]
[tex]x=180^\circ-96^\circ[/tex]
[tex]x=84^\circ[/tex]
Therefore, the value of x is 84 degrees.
