Coordinates of image (2,-4) after dilation with center of (0,0) and scale factor of 4

Cam bought some used books for $4.95. he paid $0.50 each for some books and $0.35 each for the others. he bought fewer than 8 books at each price. how many books did cam buy?

Yahir designs bracelets. he uses between 9 and 15 red and yellow beads in the ratio of 2 red bead to 5 yellow beads. drag the beads into the container to meet these requirements

Given δjkl : δxyz, find x. a)10 b)12 c)16 d)20