The sum of Rayson and his brother’s age is 29. If Rayson is 4 years older than his brother 7 years ago. How old is Rayson and his brother?

1. what are the missing reasons in the proof 2. it's in the second picture and 3

Anyone know? will mark brainliest if correct!

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?