Help solve for angle A

What can be said about the relationship between triangles and circles? check all that apply. a) many circles can be inscribed in a given triangle b) exactly one triangle can be inscribed in a given circle c) exactly one circle can be inscribed in a given triangle d) many triangular shapes can be circumscribed about a given circle

Use circumcenter theorem to solve for the given values

With both problems. a.s.a.p directions on photo ^