If eight times a certain number is subtracted from 27, the result is three. find the number

Need on this geometry question. explain how you did it.

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?

In which direction does the left side of the graph of this function point? a(x) = 3x - x2 + 4x - 2