The length of a rectangle is twice the width. The perimeter is 126 centimeters.
Which system of equations will determine the length, L, and the width, W, of the rectangle?

А.)L+2 = W
2L+ 2W = 126

B.)L+W = 2
LW = 126

C.)L=2W
21+ 2W = 126

D.)W = 2L
L+ 2W = 126

E.)2L = W
L+ W = 126

Idon’t understand this.. will someone ? will mark brainliest along with 20 points.

How do you solving the solution of each system using elimination?

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?