Answer:
Below in bold.
Step-by-step explanation:
Let the sides of the square be x units long.
The length of the diagonal = 2*4 = 8 units ( as the midpoint is 4 from vertex).
By Pythagoras:
x^2 + x^2 = 8^2
Solving for x:
2x^2 = 64
x^2 = 32
x = √32
= 4√2.
(a) Perimeter = 4 * 4√2
= 16√2 units.
(b) Area = (4√2)^2
= 16 * 2
= 32 units.
