Derive the equation for the ellipse centered at the origin with foci (0, ±2c) and vertices (0, ±2a).

The letter tiles shown below are in a bag. whiteout looking i am going to draw one tile. what are my chances of drawing g?

When i add money am i supposed to make it like this 7+12 or 7.00+12.00 because i got 19 dollars for my answer

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?