Triangle calculator SSS

Please enter the triangle side's lengths:


To calculate the properties of a triangle when given the lengths of all three sides, you can use the Law of Cosines to find the measure of each angle, and Heron's formula to find the area of the triangle.

The Law of Cosines states that:
c2 = a2 + b2 - 2ab * cos(C)

Where c is the length of the side opposite angle C, a and b are the lengths of the other two sides, and C is the measure of the angle opposite side c. You can use this formula to find the measure of each angle by plugging in the known side lengths and solving for the angle.

Once you have the measures of the angles, you can use trigonometric functions like Sine and Cosine to find the area of the triangle.

Another way to find the area of a triangle when you know the lengths of all 3 sides is to use Heron's Formula. Heron's formula states that:

Area = √(s(s-a)(s-b)(s-c))

Where s is the semi-perimeter of the triangle, which is the sum of the three side lengths divided by 2, and a, b, and c are the lengths of the three sides of the triangle.

Heron's formula allows you to find the area of a triangle even if you don't know the measures of the angles, and it works for any type of triangle, whether it's acute, right or obtuse.

If you know the special property of a triangle, use an equilateral triangle, isosceles or right triangle calculator.

Triangle SSS questions:



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See more information about triangles or more details on solving triangles.