I can help! Do you have an example problem that I can show you step by step?
Answer : 
(1) 
Use FOIL method to mulitply (3x – 5)(3x – 5)

(2) 
Use FOIL method to mulitply (3x - 5)(3x + 5)

(3) 
Use FOIL method to mulitply -(3x + 5)(3x + 5)

(4) 
Use FOIL method to mulitply -(3x + 5)(3x - 5)

So equation 2 is true
The answer is d because the perimeter of 6 by 6 would be 24 and that is the smallest perimeter.