Slope formula can prove a triangle has

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

*let m∠cob = 50°30’, m∠aob = 70° and m∠aoc = 20°30’. could point c be in the interior of ∠aob? why? a. point c could be the interior of aob but it is not the only case b. point c is the interior of aob c. point c is not the interior of aob d. the given is not possible for the plane geometry answer

Pls never taught i’m really confused and i rlly need