Explanation
The Pythagorean Theorem is used to find a missing side in a right triangle (a triangle with a 90° angle).
If we know the lengths of two sides, we can find the third side.
Formula / Rule
a² + b² = c²
Where:
- c is the hypotenuse (the longest side, opposite the 90° angle)
- a and b are the other two sides
Example
Find the hypotenuse c of a right triangle with sides a=3 and b=1.
Step 1: Substitute the values into the formula
3² + 1² = c²
Step 2: Simplify the squares
9 + 1 = c²
Step 3: Add the numbers
10 = c²
Step 4: Rewrite the equation
c² = 10
Step 5: Take the square root of both sides
c = √10
Since length is always positive, we take the positive value
Final Answer:
c = √10
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Practice
Continue Learning
- Pythagorean Formula
- Pythagoras Theorem (a² + b² = c²) – Visual Proof 1
- Pythagoras Theorem (a² + b² = c²) – Visual Proof 2
- Pythagoras Theorem (Example)