Scalene Triangle Area Calculator

Q: Are all scalene triangles acute?

No, not all scalene triangles are acute. A scalene triangle might be right, acute, or obtuse.

Q: How do I find the area of the scalene triangle with sides 3, 5, 7 inches?

The area of this triangle is 6.495 in 2 . To find the triangle area with three sides: Use Heron's formula: area = 0.25 × √[(a + b + c)(-a + b + c)(a - b + c)(a + b - c)] Knowing all three a , b , c , solve the equation. The answer is 6.495 in 2 .

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Aleksandra Zając, MD

Aleksandra Zając

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Aleksandra (Ola) Zając, MD, is a medical doctor with a passion for lifestyle medicine. She wants to never stop learning while sharing what she already knows as a health educator and prophylaxis popularizer. She mainly concentrates on how human lifestyle impacts their health and disease. After hours, she likes weightlifting, foreign affairs podcasts, learning Korean, and dogs (with a special affection for her own pup Zoja). See full profile

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Steven Wooding

Steven Wooding is a physicist by training with a degree from the University of Surrey specializing in nuclear physics. He loves data analysis and computer programming. He has worked on exciting projects such as environmentally aware radar, using genetic algorithms to tune radar, and building the UK vaccine queue calculator. Steve is now the Editorial Quality Assurance Coordinator here at Omni Calculator, making sure every calculator meets the standards our users expect. In his spare time, he enjoys cycling, photography, wildlife watching, and long walks. See full profile

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Triangles are ubiquitous in geometry, but you're in the right place if you're looking for something about scalene triangles particularly. Scalene triangle area calculator will help you find the area of the figure no matter what data you have given. Sides? Angles? Height and base? – we've covered them all with special scalene triangle area formulas. Read on and get to know more about triangles!

What is a scalene triangle?

A scalene triangle is a triangle with three sides, all of different lengths. There are no two or three sides of the same length in a scalene triangle.

Using scalene triangle area calculator

Using our tool is simple & intuitive!

In the first row, choose the mode you want to work in. It depends on which data about your triangle you know.
Let's assume we know the three sides, so we choose the mode three sides SSS (side-side-side).
Under the triangle image, we can see three empty fields. Input the lengths of the sides.
Our calculator works automatically and gives you the answer right away.
To use a different mode, just choose it in the first row. No need to clear the data.
Now you know how to use the scalene triangle area calculator!
Remember that all the scalene triangle area formulas are available in the text below in case you need them.

How do I find the area of the scalene triangle? – formulas

There are four ways to find the area of a scalene triangle. The use depends on which data you have given.

Scalene triangle area formulas with known:

Base ( $b$ ) and height ( $h$ )

\footnotesize\quad \text{area}=\frac{1}{2} \times b \times h

Three sides ( $a$ , $b$ , $c$ )

\footnotesize\quad \begin{align*} \text{area} &= \frac{1}{4} \times \sqrt{(a+b+c)}\ \times\\[1em] &\quad\sqrt{(-a+b+c)(a-b+c)}\ \times\\[1em] &\quad\sqrt{(a+b-c)} \end{align*}

Two sides and the angle between them (sides – $a$ , $b$ ; angle – $\gamma$ )

\footnotesize\quad \text{area}=\frac{1}{2} \times a \times b \times \sin(\gamma)

Two angles ( $\gamma$ , $\beta$ ) and a side between them ( $a$ )

\footnotesize\quad \text{area} = a^2\! \times \sin(\beta)\! \times\! \frac{\sin(\gamma)}{2\! \times \sin(\beta + \gamma)}

More triangle calculators

If you want to know more about triangles, check out the rest of our triangle area calculators:

FAQs

Are all scalene triangles acute?

No, not all scalene triangles are acute. A scalene triangle might be right, acute, or obtuse.

How do I calculate the scalene triangle area?

To calculate the scalene triangle area, use one of these equations:

area = 0.5 × b × h, where b – the base, h – height.
area = 0.25 × √[(a + b + c)(-a + b + c)(a - b + c)(a + b - c)], where a, b, c – triangle's sides.
area = 0.5 × a × b × sin(γ), where a, b - sides; γ – an angle between those sides.
area = a² × sin(β) × sin(γ) / (2 × sin(β + γ)), where β, γ – angles, a – side between those angles.

How do I find the area of the scalene triangle with sides 3, 5, 7 inches?

The area of this triangle is 6.495 in². To find the triangle area with three sides:

Use Heron's formula:
area = 0.25 × √[(a + b + c)(-a + b + c)(a - b + c)(a + b - c)]
Knowing all three a, b, c, solve the equation.
The answer is 6.495 in².

How many sides are equal in a scalene triangle?

There are no equal sides in a scalene triangle. A scalene triangle is a triangle with three unequal sides.