Please explain. If you explain for B and answer for A i will give you brainist answer

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.

Write the sine and cosine values of a, b, respectively, in the figure for (1) and (2) + explanation.

3x = 729 solve for x plz . it's urgent. will mark