3. Angle A in triangle ABC is obtuse. Can angle B or angle C be obtuse? Explain your reasoning
No. To be obtuse the angle has to be over 90 degrees. All triangles should add up to 180 degrees. If angle A is at the smallest degree it can be (90) then that leaves 90 degrees to be split between angle B and C. Therefore they would have to both be less than 90 degrees making them both acute angles.