Help I NEED HELP
PLS THIS NEED TO BE CHECKED TOMORROW I HOPE THERES SOMEONE WILL HELP (MATH)

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.

Idon't get undoing if its pass adding and subtracting so can someone ? x-2 over 5 = 18

The product of (7x-2) and (20-3x)/4. when x=4