Answer:
not similar
Explanation:
You want to know if two isosceles triangles are similar, given that one has a base angle of 78°, and the other has an a.pex angle of 16°.
Base angle
The base angles of the triangle with a.pex angle 16° will be ...
(180° -16°)/2 = 82° . . . . . . not 78°
Similarity
Two isosceles triangles will be similar if they have congruent base angles. These triangles do not, so they are not similar.