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Rectangle Calculator — Area, Perimeter & Diagonal

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Calculated result

Area 108

Perimeter: 42

Diagonal: 15

Aspect ratio: 4:3

Show the working
  1. 1. Area = 12 × 9 = 108.
  2. 2. Perimeter = 2(12 + 9) = 42.
  3. 3. Diagonal = √(12² + 9²) = 15.

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