Which of the sets of ordered pairs represents a function? a = {(1, −5), (8, −5), (8, 7), (2, 9)} b = {(7, −4), (7, −2), (6, −3), (−9, 5)} only a only b both a and b neither a nor b

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.

Erin bought christmas cards for $2 each to send to her family and friends. which variable is the dependent variable?

The? half-life of a radioactive substance is 20 years. if you start with some amount of this? substance, what fraction will remain in 120 ? years