Maria cycled a total distance of 66,528 ft on a bicycle path surrounding a lake. She cycled 9 laps, where each lap was the same length. What was the length of
each lap around the lake? Write your answer in miles.

In a probability experiment, karen flipped a coin 76 times. the coin landed on heads 32 times. what percentage of the coin flips resulted in tails? round to the nearest percent. a. 58% b. 65% c. 42% d. 60%

Factor the polynomial 4x4 – 20x2 – 3x2 + 15 by grouping. what is the resulting expression? (4x2 + 3)(x2 – 5) (4x2 – 3)(x2 – 5) (4x2 – 5)(x2 + 3) (4x2 + 5)(x2 – 3)

Prove (a) cosh2(x) − sinh2(x) = 1 and (b) 1 − tanh 2(x) = sech 2(x). solution (a) cosh2(x) − sinh2(x) = ex + e−x 2 2 − 2 = e2x + 2 + e−2x 4 − = 4 = . (b) we start with the identity proved in part (a): cosh2(x) − sinh2(x) = 1. if we divide both sides by cosh2(x), we get 1 − sinh2(x) cosh2(x) = 1 or 1 − tanh 2(x) = .