Let
Length of rectangle be "x"
Width of rectangle be "y"
Given, length is 3 more than twice width, we can write:

Also, given the perimeter is 102.
Recall, perimeter is sum of all the sides of a rectangle. Thus, we can write:

Substituting, equation 1 into equation 2, we get:

Multiplying out and solving for y:

Now, x is:

Answer:
The length is 35 and width is 16