(1/4+1/4)-6÷1/3+2 how do you get it​

The equation respenting the left table is

If f(x) =3x-2 and g(x) =2x+1 fins (f+ g) (x)

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?