Geometry Conclusions
1. Statement 36: The perpendiculars drawn from the vertices of a triangle to the opposite sides are known as the altitudes of the triangle.
Conclusion I: The line segments joining the vertices to the midpoint of opposite sides of a triangle are always perpendicular on that side and are called medians of the triangle.
- This conclusion is incorrect because medians join vertices to midpoints but are not necessarily perpendicular to the opposite sides.
Conclusion II: The point of the intersection of the three perpendiculars is known as the centroid.
- This conclusion is incorrect; the intersection of altitudes is called the orthocenter, not the centroid.
2. Statement 37: A chord which passes through the centre of the circle is called the diameter of the circle.
Conclusion I: The diameter is the longest chord of the circle.
- This conclusion is correct because the diameter passes through the center and is the longest possible chord.
Conclusion II: Diameter divides the circle into a major and a minor segment.
- This conclusion is incorrect; the diameter divides the circle into two equal semicircles, not major and minor segments.
3. Statement 38: A line segment with both the endpoints lying on the circle is called the chord of the circle.
Conclusion I: A chord of a circle divides the circle into two parts. Each part is called a sector of the circle.
- This conclusion is incorrect; the two parts are called segments, not sectors.
Conclusion II: A tangent can act as a chord but a chord can never act as a tangent.
- This conclusion is incorrect; a tangent touches the circle at exactly one point and cannot be a chord, which has two endpoints on the circle.
4. Statement 39: The area bounded by two radii and their corresponding arc is called the sector of a circle.
Conclusion I: The diameter of a circle divides the circle into two exactly equal sectors.
- This conclusion is correct; the diameter divides the circle into two semicircular sectors.
Conclusion II: If the arc of a sector is less than the semicircle, then it is called the major sector.
- This conclusion is incorrect; if the arc is less than a semicircle, the sector is called a minor sector.
5. Statement 40: The sum of the angles of a triangle is always 180°.
Conclusion I: A triangle in which one of the angles measures 90° is called a right-angled triangle or simply a right triangle.
- This conclusion is correct.
Conclusion II: A triangle cannot have two or more right angles.
- This conclusion is correct because the sum of angles is 180°, so two right angles would exceed this.
Final summary:
- Correct conclusions: 37.I, 39.I, 40.I, 40.II
- Incorrect conclusions: 36.I, 36.II, 37.II, 38.I, 38.II, 39.II