Find cos(2θ) if tan(θ) = -3/4 and 90 < θ < 180

What is the sum or difference 4x10 – 9x10 (1 point) –5x10 –5x20 –36x10 –36x20 this is the cca test i need all the answers this is the first 2

Suppose i flip two identical coins. what is the probability that i get one head and one tail?

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.