Answer:
The triangles SYX and SYZ are congrient so by CPCTC
,
and
.
Explanation:
Given information: YS is the perpendicular bisector of XYZ.
In triangle YXS and triangle YSZ,
(YS is the perpendicular bisector of XYZ)
(Common side, Reflexive property)
(YS is the perpendicular bisector of XYZ)
By ASA postulate,

The corresponding parts of congruent triangles are congruent. so,


