Calculate the sides of a right triangle using the Pythagorean theorem (a² + b² = c²). Find the hypotenuse or any leg given two sides.
Hypotenuse c
5.0000
Pythagorean Triple!
3.00² + 4.00² = 5.00²
9.00 + 16.00 = 25.00
Step 1: Square both legs
a² = 3² = 9.0000
b² = 4² = 16.0000
Step 2: Add the squares
a² + b² = 9.0000 + 16.0000 = 25.0000
Step 3: Take the square root
c = √25.0000 = 5.0000
6.00
Area
12.00
Perimeter
36.9°
Angle A
53.1°
Angle B
Note: Angle A is opposite side a, Angle B is opposite side b, and the right angle (90°) is opposite the hypotenuse c.
Click any triple to use those values in the calculator.
Hypotenuse c
5.0000
Pythagorean Triple!
3.00² + 4.00² = 5.00²
9.00 + 16.00 = 25.00
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The Pythagorean theorem states that in a right triangle, a2 + b2 = c2, where c is the hypotenuse (longest side, opposite the right angle) and a and b are the two legs. To find the hypotenuse: c = sqrt(a2 + b2). To find a leg: a = sqrt(c2 - b2). Common Pythagorean triples: 3-4-5, 5-12-13, 8-15-17.
The Pythagorean theorem is a fundamental principle in geometry stating that in a right triangle, the square of the hypotenuse (the side opposite the right angle) equals the sum of the squares of the other two sides. This relationship, expressed as a2 + b2 = c2, is used in construction, navigation, surveying, and countless mathematical applications.
The Pythagorean theorem states that in a right triangle, a2 + b2 = c2, where c is the hypotenuse (longest side, opposite the right angle) and a and b are the two legs. To find the hypotenuse: c = sqrt(a2 + b2). To find a leg: a = sqrt(c2 - b2). Common Pythagorean triples: 3-4-5, 5-12-13, 8-15-17.
The Pythagorean theorem states that in a right triangle, the square of the hypotenuse (the longest side, opposite the right angle) equals the sum of the squares of the other two sides. Written as: a² + b² = c², where c is the hypotenuse.
A Pythagorean triple is a set of three positive integers (a, b, c) that satisfy a² + b² = c². Common examples include (3, 4, 5), (5, 12, 13), (8, 15, 17), and (7, 24, 25). Multiples of triples are also triples: (6, 8, 10).
To find the hypotenuse (c), use the formula c = √(a² + b²). Square both legs, add them together, and take the square root. For example, with legs 3 and 4: c = √(9 + 16) = √25 = 5.
To find a leg (a) when you know the other leg (b) and hypotenuse (c): a = √(c² - b²). Subtract the square of the known leg from the square of the hypotenuse, then take the square root.
Common uses include: calculating distances on maps, determining diagonal screen sizes, construction and carpentry (ensuring right angles), navigation, physics problems, and computer graphics. Any problem involving right triangles can use this theorem.
Last updated: 2025-01-15
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Hypotenuse c
5.0000
Pythagorean Triple!
3.00² + 4.00² = 5.00²
9.00 + 16.00 = 25.00