Answer:
The angles
are used to prove the similarity of triangles VWZ and YXZ.
Step-by-step explanation:
Given information: 
Two triangles are called congruent if their corresponding sides are in same proportion or the corresponding angles are same.
If two corresponding sides of triangle have same proportion and their inclined angle is same, then by SAS rule of similarity both triangles are similar.
From the given figure it is noticed that the ∠VZW and ∠YZX are vertically opposite angles. The vertically opposite angles are always equal.
(Vertically opposite angles)
(Given)
By SAS rule of similarity

Therefore the angles
are used to prove the similarity of triangles VWZ and YXZ.
You are correct the answer is a:18
Answer:
-9.85
Step-by-step explanation:
-15.5 - 4.2 = -19.7
Negatives work like positives
19.7 / 2 = 9.85
Turn that into a negative
-9.85
Answer:
I think it would be 40?
Step-by-step explanation:
I think 40 because if I recall correctly, to find the range you must subtract the max from the min, the max being 100 and the min being 60 in this case.