Can someone me with this? it'll be greatly appreciated

Through non-collinear points there is exactly one plane.

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).

Analyze the diagram below and complete the instructions that follow. 56 find the unknown side length, x write your answer in simplest radical form. a 2047 b. 60 c. sv109 d. 65 save and exit next s and return