Which equation can be used to solve for x in the following diagram

Sketch one cycle if the cosine function y=2cos2theta

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.

If i have 20$ and i gave 5$ away how much i got