What is the difference of the polynomials? (5x3 + 4x2) – (6x2 – 2x – 9) –x3 + 6x2 + 9 –x3 + 2x2 – 9 5x3 – 2x2 – 2x – 9 5x3 – 2x2 + 2x + 9

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?