Answer:
- √2
- 8
Explanation:
The diagonal of a square is √2 times the side length.
1.
For BD = 4, AD = 4/√2 and AE is half that, or 2/√2 = √2.
The length of AE is √2.
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2.
The area of the square is the square of the side length:
Area = AE² = (2√2)² = 8
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Additional comment
The area of a quadrilateral in which the diagonals are perpendicular is found to be half the product of the diagonal lengths. Here, that would be ...
1/2(4)(4) = 8 . . . square units