What Is Heron’s Formula With Example?

When it comes to calculating the area of a triangle without the height, Heron’s formula comes to the rescue. This formula is named after Hero of Alexandria, a mathematician from ancient Greece, who is credited with its discovery. Heron’s formula allows us to compute the area of a triangle based on the lengths of its three sides.

To understand Heron’s formula, we must first comprehend its components. Let’s consider a triangle with sides of lengths a, b, and c. The formula states that the area (A) of the triangle is equal to the square root of s multiplied by (s – a) multiplied by (s – b) multiplied by (s – c), where s is the semi-perimeter of the triangle.

Now, what exactly is the semi-perimeter? The semi-perimeter (s) of a triangle is calculated by adding the three sides together and dividing the sum by 2. In other words, s = (a + b + c) / 2. This value plays a crucial role in Heron’s formula and simplifies the computation of the triangle’s area.

When we substitute the values of the sides of the triangle and the semi-perimeter into the formula, we can easily determine the area of the triangle. Let’s consider an example to illustrate this. Suppose we have a triangle with side lengths of 5, 12, and 13 units.

Calculating the semi-perimeter first, we find that s = (5 + 12 + 13) / 2 = 15 units. Substituting this value into Heron’s formula gives us A = √(15(15 – 5)(15 – 12)(15 – 13)).

Solving this expression step by step, we get A = √(15*10*3*2) = √900 = 30 square units. Therefore, the area of the triangle with side lengths 5, 12, and 13 is 30 square units.

It is important to note that Heron’s formula is particularly useful when the height of a triangle cannot be easily determined. By solely knowing the lengths of the sides, we can apply this formula to find the area accurately.

Furthermore, Heron’s formula is not limited to right-angled triangles; it can be applied to any triangle, regardless of its angles. This versatility makes the formula a valuable tool in geometry for calculating areas efficiently.

In conclusion, Heron’s formula provides a straightforward method for determining the area of a triangle based on its side lengths. By understanding the concept of the semi-perimeter and following the formula correctly, we can easily compute the area of any triangle without the need for its height.

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Don Atkins

Don Atkins is a proud Canadian and experienced biology teacher living in Toronto. With a Bachelor of Science in Biology from the University of Saskatchewan under his belt, Don has 10 years of teaching experience and is passionate about sharing his knowledge with others. He also volunteers at the Northeastern Avian Rescue, using his expertise to help birds in need. Don's enthusiasm for ornithology is undeniable, and he loves nothing more than to share it with those around him.