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Diameter of a Rectangle Calculator

Rectangle Diagonal Formula:

\[ d = \sqrt{l^2 + w^2} \]

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1. What is the Rectangle Diagonal Formula?

The diagonal of a rectangle can be calculated using the Pythagorean theorem, which states that in a right-angled triangle, the square of the hypotenuse (diagonal) is equal to the sum of the squares of the other two sides (length and width).

2. How Does the Calculator Work?

The calculator uses the diagonal formula:

\[ d = \sqrt{l^2 + w^2} \]

Where:

Explanation: The formula is derived from the Pythagorean theorem, where the diagonal forms the hypotenuse of a right triangle with the length and width as the other two sides.

3. Importance of Diagonal Calculation

Details: Calculating the diagonal is important in various fields like construction, design, and engineering. It helps determine the longest straight-line distance within a rectangular space, which is crucial for fitting objects, determining screen sizes, and structural calculations.

4. Using the Calculator

Tips: Enter the length and width of the rectangle in any consistent units (inches, centimeters, meters, etc.). Both values must be positive numbers. The result will be in the same units as your input.

5. Frequently Asked Questions (FAQ)

Q1: Is the diagonal the same as the diameter?
A: While similar in concept, diameter typically refers to circles, while diagonal refers to polygons. For rectangles, the diagonal serves a similar purpose as diameter does for circles.

Q2: Does this work for squares?
A: Yes, for squares (where length = width), the formula simplifies to \( d = l\sqrt{2} \).

Q3: Can I use this for 3D boxes?
A: For a rectangular prism, you would need a different formula: \( d = \sqrt{l^2 + w^2 + h^2} \), where h is the height.

Q4: What units should I use?
A: Any consistent units can be used (inches, cm, meters, etc.), as long as both length and width are in the same units.

Q5: How accurate is this calculation?
A: The calculation is mathematically exact for perfect rectangles. Real-world accuracy depends on how precisely you can measure the length and width.

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