The equations of four lines are given. Identify which lines are parallel. Line 1: y=1/2x-6. Line 2: x-2y=-1. Line 3: y=4x+6. Line 4: y+3=1/4(x-6)

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?