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Altitudes and Orthocentre
The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a right triangle it sits at the right-angle vertex (the two legs are already altitudes). In an obtuse triangle it lies outside, because two altitudes fall on extensions of the sides.
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Altitudes and Orthocentre
What is it?
The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a right triangle it sits at the right-angle vertex (the two legs are already altitudes). In an obtuse triangle it lies outside, because two altitudes fall on extensions of the sides.
In simple words
- The three altitudes meet at the orthocentre.
- orthocentre
- inside
- right-angle vertex
Important terms
Altitudes And Orthocentre: The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a right triangle it sits at the right-angle vertex (the two legs are already altitudes). In an obtuse triangle it lies outside, because two altitudes fall on extensions of the sides.
What you should learn
- Define and explain altitudes and orthocentre.
- Apply altitudes and orthocentre to a focused FBISE question.
- Check the answer for correct terms, evidence, working, and units.
Examples
- orthocentre
- inside
- right-angle vertex
CORE UNDERSTANDING
The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a right triangle it sits at the right-angle vertex (the two legs are already altitudes). In an obtuse triangle it lies outside, because two altitudes fall on extensions of the sides.
EXAM APPLICATION
State the correct term, connect it to the chapter rule or evidence, and use a clear example or calculation.
Recommended for Class 9
Full school-level explanation
The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a right triangle it sits at the right-angle vertex (the two legs are already altitudes). In an obtuse triangle it lies outside, because two altitudes fall on extensions of the sides.
Learn the idea, then use it:
WHAT — ALTITUDES AND ORTHOCENTRE
The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a right triangle it sits at the right-angle vertex (the two legs are already altitudes). In an obtuse triangle it lies outside, because two altitudes fall on extensions of the sides.
HOW — Use the idea
Identify what is given, select this topic's rule or evidence, apply it one step at a time, and check the result.
CORE UNDERSTANDING
The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a right triangle it sits at the right-angle vertex (the two legs are already altitudes). In an obtuse triangle it lies outside, because two altitudes fall on extensions of the sides.
Remember
- orthocentre
- inside
- right-angle vertex
Examples
- orthocentre
- inside
- right-angle vertex
- ALTITUDES AND ORTHOCENTRE: The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a right triangle it si
EXAM APPLICATION
State the correct term, connect it to the chapter rule or evidence, and use a clear example or calculation.
Remember
- correct term
- chapter link
- clear application
Examples
- Define first
- Show the rule or evidence
- Check units, labels, and conclusion
Remember
- orthocentre
- inside
- right-angle vertex
- keep the ideas separate
- orthocentre
- inside
- right-angle vertex
- correct term
Deeper understanding
Go beyond memorising Altitudes and Orthocentre. Connect the definition to reasons, relationships, exceptions, and exam wording.
Common mistakes
Exam focus
Core Idea
Key Points
Simple Check
How to Answer
Exam focus
Quick revision
- orthocentre
- inside
- right-angle vertex
- keep the ideas separate
- Altitudes And Orthocentre: The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a
- WHAT — ALTITUDES AND ORTHOCENTRE: The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a
Do not merge altitudes and orthocentre with a neighbouring idea that uses a different definition, rule, or method.
For long answers on Altitudes and Orthocentre: define clearly → explain the main parts → give one example → state one exam caution.
Exam Focus
Exam Focus
Important points
- orthocentre
- inside
- right-angle vertex
- keep the ideas separate
Important formulas
- orthocentre
- inside
- right-angle vertex
Common exam traps
- Do not merge altitudes and orthocentre with a neighbouring idea that uses a different definition, rule, or method.
- Do not invent a formula, fact, unit, or diagram label that the chapter does not support.
Long question structure
Definition → key parts → example → exam caution
Common Mistakes
Common Mistakes
- Mistake
Do not merge altitudes and orthocentre with a neighbouring idea that uses a different definition, rule, or method.
- Mistake
Do not invent a formula, fact, unit, or diagram label that the chapter does not support.
- Mistake
Do not merge altitudes and orthocentre with a neighbouring idea that uses a different definition, rule, or method.
Revision Zone
60-Second Revision
Quick cues from this topic — use them for last-minute revision.
orthocentre
inside
right-angle vertex
keep the ideas separate
The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a right triangle it sits at the right-angle vertex (the two le
- Definition
- The three altitudes meet at the orthocentre. In an acute triangle the orthocentre lies inside. In a right triangle it sits at the right-angle vertex (the two le
- Example
- orthocentre
- Critical warning
- Do not merge altitudes and orthocentre with a neighbouring idea that uses a different definition, rule, or method.
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Exam Practice
Define
Q1. Define Altitudes and Orthocentre.
Explain
Q2. Explain: CORE UNDERSTANDING.
Example
Q3. Give one clear example of Altitudes and Orthocentre and say why it fits.
Mistake
Q4. State one common mistake students make about Altitudes and Orthocentre.
Exam note
Q5. Write a short exam note on Altitudes and Orthocentre: definition, two points, one example.
Sources & References
School-standard facts for Matric and Intermediate. Original explanations — not copied from textbooks.