The line a and line b are parallel to each other since if you draw another line or a third plane and it contains both points both in line a and in line b it means that this third plane passes through to the both lines a and b. In order to achieve both lines a and b can be passed by the third plane, they should be parallel to each other.
A rectangle is a two-dimensional shape with two sets of equal, parallel sides. These dimensions are the length (L) and the width (W). The formula for the rectangle's area is the product of the two dimensions. The formula for perimeter is
P = 2L + 2W
Since
A = LW = 64
W = 64/L
Substituting to the formula for perimeter would be,
P = 2L + 2(64/L)
P = 2L + 128/L
