What is the difference of the polynomials (86^6s^3-9r^5s^4+3r^4s^5) -(2r^4s -5r^3s^6 - 4r^5s^4

What could explain what happened when the time was equal to 120 minutes

Suppose a pendulum is l meters long. the time,t,in seconds that it tales to swing back and forth once is given by t=2.01

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.