Length of the hypotenuse
I can use Pythagoras' theorem to find the length of the hypotenuse.
Length of the hypotenuse
I can use Pythagoras' theorem to find the length of the hypotenuse.
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Lesson details
Key learning points
- The sum of the squares of the two shorter sides equals the square of the longest side.
- The longest side is always opposite the right angle.
- A calculator can perform these calculations efficiently.
- Priority of operations makes the order clear.
Keywords
Pythagoras’ theorem - Pythagoras’ theorem shows that the sum of the squares of the two shorter sides of a right-angled triangle is equal to the square of its longest side (the hypotenuse).
Hypotenuse - A hypotenuse is the side of the right-angle triangle which is opposite the right-angle.
Right-angled triangle - A right-angled triangle has exactly one 90° interior angle.
Common misconception
Pythagorean triples can be a trio of any rational numbers that, when constructed into a triangle, always produces a right-angled triangle.
Pythagorean triples are conventionally a trio of integer side lengths of a right-angled triangle, such as the 3, 4, 5 triangle. Other, similar triangles can be generated from Pythagorean triples, whose side lengths are rational, such as 0.3, 0.4, 0.5
To help you plan your year 9 maths lesson on: Length of the hypotenuse, download all teaching resources for free and adapt to suit your pupils' needs...
To help you plan your year 9 maths lesson on: Length of the hypotenuse, download all teaching resources for free and adapt to suit your pupils' needs.
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Explore more key stage 3 maths lessons from the Geometrical properties: similarity and Pythagoras' theorem unit, dive into the full secondary maths curriculum, or learn more about lesson planning.
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Starter quiz
6 Questions
Exit quiz
6 Questions
