Answer:
z = 8.5
Step-by-step explanation:
Let O be the center of the circle, and A, B, C are three points on the circle.
Draw OA and OC are shown in the figure. To make the central angle.
In the figure the measure of arc AC is 118 degrees. measure of central angle and subtrahend arc is same. So, central angle is
[tex]\angle AOC=118^{\circ}[/tex]
Subtended angle on arc AC is
[tex]\angle ABC=(6z+8)^{\circ}[/tex]
According to central angle theorem of circle, central angle is twice of angle subtended by the arc.
[tex]\angle AOC=2\times \angle ABC[/tex]
[tex]118^{\circ}=2\times (6z+8)^{\circ}[/tex]
[tex]118=12z+16[/tex]
[tex]118-16=12z[/tex]
[tex]102=12z[/tex]
[tex]\dfrac{102}{12}=z[/tex]
[tex]8.5=z[/tex]
Therefore, the value of z is 8.5.