ANSWER
a. d+4
b. 4d+16
EXPLANATION
The area of the square coaster is represented by:

We split the middle term to obtain,

We factor by grouping to get,


Since area of a square is l² , it means the side length of the square is

b) The perimeter of a square is given by

We substitute the length in terms of d, to obtain;

Or

Square roots are rational and it equals 5 and 5 is rational
Answer:
Identity
Step-by-step explanation: