I'm not sure but I think it is the first one
Answer:
60°
Step-by-step explanation:
Total angle measurement for a triangle is 180°
Equilateral triangle measures 60 on all angles. (60 + 60 + 60 = 180°)
This triangle is equilateral so it's angle is 60°.
Why is it equilateral? Because all sides of the triangle are equal (10 on all sides).
Hope this helps
Supplementary because the add to 180°
Answer:

The domain of the inverse of a relation is the same as the range of the original relation. In other words, the y-values of the relation are the x-values of the inverse.
Thus, domain of f(x): x∈R = range of f¯¹(x)
and range of f(x): x∈R =domain of f¯¹(x)
True a goal is something that should be simple and easy