-10.5 can one of the addends be positive and the other be negative? Provide an example to prove your answer

Write an explicit formula that represents the sequence defined by the following recursive formula:

Which undefined geometric term is described as a location on a coordinate plane that is designed by an ordered pair (x, y) ?

In the figure below, ∠dec ≅ ∠dce, ∠b ≅ ∠f, and segment df is congruent to segment bd. point c is the point of intersection between segment ag and segment bd, while point e is the point of intersection between segment ag and segment df. the figure shows a polygon comprised of three triangles, abc, dec, and gfe. prove δabc ≅ δgfe.