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Isosceles Triangle Height Calculator

Isosceles Triangle Height Formula:

\[ h = \sqrt{leg^2 - \left(\frac{base}{2}\right)^2} \]

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1. What is an Isosceles Triangle?

An isosceles triangle is a triangle with two sides of equal length (the legs) and a third side of different length (the base). The height (altitude) of an isosceles triangle is the perpendicular distance from the base to the opposite vertex.

2. How Does the Calculator Work?

The calculator uses the isosceles triangle height formula:

\[ h = \sqrt{leg^2 - \left(\frac{base}{2}\right)^2} \]

Where:

Explanation: The formula is derived from the Pythagorean theorem, where the height forms a right triangle with half of the base and one leg.

3. Importance of Height Calculation

Details: Calculating the height of an isosceles triangle is essential for determining its area, understanding its geometric properties, and solving various geometric problems in mathematics, engineering, and architecture.

4. Using the Calculator

Tips: Enter the length of the equal sides (legs) and the base length in any consistent units. Both values must be positive numbers, and the leg length must be greater than half of the base length.

5. Frequently Asked Questions (FAQ)

Q1: What if my triangle has all three sides equal?
A: That would be an equilateral triangle, which is a special case of isosceles triangle. The formula still works but you can use the simpler equilateral triangle height formula.

Q2: Can I use this calculator for right triangles?
A: No, right triangles have a different method for calculating height. This calculator is specifically for isosceles triangles.

Q3: What units should I use?
A: You can use any units (cm, inches, meters, etc.) as long as both measurements are in the same units.

Q4: Why does the leg need to be longer than half the base?
A: This is a geometric requirement for a valid triangle. If leg ≤ base/2, the sides couldn't meet to form a triangle.

Q5: How can I calculate the area once I have the height?
A: The area of an isosceles triangle is (base × height)/2.

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