SIDE a
ACTIVE
SIDE b
TAP
HYP c
AUTO
RESULT
AUTO
PYTHAGORAS CALCULATOR
Choose the missing side of a right triangle and see the square root working
Useful for GCSE maths, right triangle side checks and Pythagoras revision
WORKING
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PAGE SUMMARY
Use this page to find a missing side in a right triangle with Pythagoras.
If the missing side is the hypotenuse, the calculator adds the two leg squares.
If the missing side is a leg, the calculator subtracts one square from the hypotenuse square.
This is useful for GCSE maths, right triangle checks and revision of square root working.
Extra help, worked examples and related links are on the next pages.
Page 1 stays focused on the calculator so the keypad and controls remain clear on laptops and phones.
PYTHAGORAS FORMULA
c² = a² + b²
c is the hypotenuse, the longest side opposite the right angle.
a and b are the two shorter sides of the right triangle.
FINDING THE HYPOTENUSE
c = √(a² + b²)
Square both shorter sides, add them, then take the square root.
FINDING A SHORTER SIDE
a = √(c² − b²)
b = √(c² − a²)
Square the hypotenuse, subtract the known shorter side square, then take the square root.
KEYPAD HELP
NEXT moves between the two editable boxes.
BS deletes, CLR clears the current box and C resets the full page.
SWAP swaps the two known values.
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WORKED EXAMPLE: FIND c
Given a = 6 and b = 8
c² = 6² + 8²
c² = 36 + 64 = 100
c = √100 = 10
WORKED EXAMPLE: FIND a
Given c = 10 and b = 8
a² = 10² − 8²
a² = 100 − 64 = 36
a = √36 = 6
WORKED EXAMPLE: FIND b
Given c = 10 and a = 6
b² = 10² − 6²
b² = 100 − 36 = 64
b = √64 = 8
WHEN IT WORKS
Pythagoras is for right triangles only.
When finding a or b, the hypotenuse must be larger than the other known side.
Otherwise the value inside the square root becomes negative.
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PYTHAGORAS GCSE HELP
This page is designed for right triangle side questions in GCSE maths.
It suits searches for Pythagoras calculator, hypotenuse calculator and missing side right triangle calculator.
COMMON SEARCH TOPICS
pythagoras calculator
find the hypotenuse
right triangle missing side
gcse pythagoras help
RELATED PAGES
LOOP BACK
Use NEXT to return to Page 1 and solve another triangle straight away.
That keeps the calculator page clean while still giving stronger help and SEO pages.
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SIDE a
ACTIVE
SIDE b
TAP
HYP c
AUTO
RESULT
AUTO
WORKING
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PAGE 1/4
PYTHAGORAS FORMULA
c² = a² + b²
c is the hypotenuse.
a and b are the two shorter sides of a right triangle.
FINDING c
c = √(a² + b²)
Square the two known shorter sides, add them, then square root the answer.
FINDING a OR b
a = √(c² − b²)
b = √(c² − a²)
Square the hypotenuse, subtract the known shorter side square, then square root the result.
KEYPAD
NEXT moves between the two editable boxes.
BS deletes, CLR clears the current box and C resets the page.
SWAP swaps the two known values.
PAGE 2/4
FIND c EXAMPLE
a = 6, b = 8
c² = 6² + 8² = 36 + 64 = 100
c = √100 = 10
FIND a EXAMPLE
c = 10, b = 8
a² = 10² − 8² = 100 − 64 = 36
a = √36 = 6
FIND b EXAMPLE
c = 10, a = 6
b² = 10² − 6² = 100 − 36 = 64
b = √64 = 8
IMPORTANT CHECK
This method works for right triangles only.
When finding a or b, the hypotenuse must be larger than the known shorter side.
PAGE 3/4
PYTHAGORAS GCSE HELP
This page helps with right triangle side calculations using Pythagoras.
It suits searches for Pythagoras calculator, right triangle missing side calculator and hypotenuse finder.
COMMON SEARCHES
pythagoras calculator
find the hypotenuse
right triangle missing side
gcse pythagoras help
RELATED PAGES
LOOP BACK
Use NEXT to return to Page 1 and solve another right triangle.
PAGE 4/4