Please help I just need the equation

Asegment in the complex plane has a midpoint at 7 – 2i. if the segment has an endpoint at 11 – 3i, what is the other endpoint?

*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

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?