#### Question

Let U be the set of all triangles in a plane. If A is the set of all triangles with at least one angle different from 60°, what is A'

#### Solution

A' is the set of all equilateral triangles.

Is there an error in this question or solution?

Solution Let U Be the Set of All Triangles in a Plane. If a is the Set of All Triangles with at Least One Angle Different from 60°, What is A' Concept: Complement of a Set.