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Triangle Calculator
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Triangle Calculator
Calculate triangle properties including area, perimeter, angles, and sides.
Calculate Triangle
Calculation Method
SSS - Three Sides
SAS - Two Sides and Included Angle
ASA - Two Angles and Included Side
Side A
Side B
Side C
Calculate
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Triangle Properties
Triangle Types
Acute Triangle
All angles < 90°
Right Triangle
One angle = 90°
Obtuse Triangle
One angle > 90°
Equilateral
All sides equal
Isosceles
Two sides equal
Formulas Used
Law of Cosines:
c² = a² + b² - 2ab cos(C)
Law of Sines:
a/sin(A) = b/sin(B) = c/sin(C)
Heron's Formula:
Area = √[s(s-a)(s-b)(s-c)]
where s = (a+b+c)/2
Special Cases
Right Triangle:
a² + b² = c² (Pythagorean theorem)
Equilateral Triangle:
All angles = 60°, Area = (√3/4) × side²
30-60-90 Triangle:
Sides in ratio 1 : √3 : 2
45-45-90 Triangle:
Sides in ratio 1 : 1 : √2