XWZ is a central angle; the measure of the arc intersected by a central angle is equal to the measure of the arc.
Intersected arc XZ:
[tex]mXZ=115°[/tex]
The total circumference (total arc) in a circle is 360°, use it and the measure of arc XZ to find the measure of arc XYZ:
[tex]\begin{gathered} mXYZ+mXZ=360 \\ \\ mXYZ=360-mXZ \\ mXYZ=360-115 \\ mXYZ=245 \end{gathered}[/tex]Then, the measure of XZ is 115° and the measure of XYZ is 245°
