Difficulty: Easy
Correct Answer: centroid
Explanation:
Introduction / Context:
This is a conceptual geometry question that tests your knowledge of special points associated with a triangle. Each of the four classical centres (centroid, orthocentre, incentre, and circumcentre) is defined in a different way. Here we focus specifically on medians and their point of concurrency.
Given Data / Assumptions:
Concept / Approach:
It helps to recall the definitions:
Centroid: Intersection point of the three medians.
Orthocentre: Intersection point of the three altitudes.
Incentre: Intersection point of the three internal angle bisectors.
Circumcentre: Intersection point of the perpendicular bisectors of the sides.
Recognising which construction is described in the question immediately leads to the correct term.
Step-by-Step Solution:
The question explicitly mentions medians.
By definition, medians connect each vertex to the midpoint of the opposite side.
The unique point at which all three medians of a triangle meet is called the centroid.
Therefore, the point of intersection of all the three medians is the centroid.
Verification / Alternative check:
In coordinate geometry, if the vertices of a triangle are (x1, y1), (x2, y2), and (x3, y3), the intersection of the medians is at the point whose coordinates are:
((x1 + x2 + x3) / 3, (y1 + y2 + y3) / 3)
This point is well known as the centroid and lies two-thirds of the way from each vertex along the median, supporting our identification.
Why Other Options Are Wrong:
Orthocentre involves altitudes, not medians. Incentre uses angle bisectors, and circumcentre uses perpendicular bisectors of the sides. None of these definitions match the description given in the question.
Common Pitfalls:
Students sometimes mix up the various triangle centres because their names sound similar. The key is to link each centre with its defining construction: medians for centroid, altitudes for orthocentre, and so on. Drawing a simple triangle and sketching the lines helps fix the concept visually.
Final Answer:
The point of intersection of all the medians is called the centroid of the triangle.
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