Write the equation of the circle: center at (0,0), diameter 18

Kayla wants to find the width, ab, of a river. she walks along the edge of the river 65 ft and marks point c. then she walks 25 ft further and marks point d. she turns 90° and walks until her location, point a, and point c are collinear. she marks point e at this location, as shown. (a) can kayla conclude that δ and δ are similar? why or why not? (b) suppose de = 15 ft. what can kayla conclude about the width of the river?

Suppose you just purchased a digital music player and have put 8 tracks on it. after listening to them you decide that you like 4 of the songs. with the random feature on your player, each of the 8 songs is played once in random order. find the probability that among the first two songs played (a) you like both of them. would this be unusual? (b) you like neither of them. (c) you like exactly one of them. (d) redo () if a song can be replayed before all 8 songs are played.

Simplify (4x^2 - 8xy + 2y^2) - (9x^2 - 4xy - 7y^2) a. -5x^2 + 4xy + 9y^2 b. -5x^2 - 4xy + 9y^2 c. -5x^2 + 12xy + 4y^2 d. -5x^2 - 4xy - 5y^2