I Can’t figure these 3 questions out can someone help me please!

Answer:
Number 9 is 8, 8 is the length of each side
Step-by-step explanation:
8 x 8 = 64
And it s a square so all sides are equal
Answer: 8 feet long
Step-by-step explanation:
this is because a square has 4 sides that are all the same length
and the formula for area of a square is A = base x height
since you are given the height you would take the sqrt of 64 and get 8
8 x 8 = 64