In a triangle, the sum of the lengths of either two sides is always greater than the third side.
(i) Given that, the sides of the triangle are \(2 \;cm, 3 \;cm, 5 \;cm\).
It can be observed that,
\(2 + 3 = 5\) \(cm\)
However, \(5\) \(cm\) = \(5\) \(cm\)
Hence, this triangle is not possible.
(ii) Given that, the sides of the triangle are \(3\; cm, 6\; cm, 7 \;cm\).
Here, \(3 + 6 = 9\) \(cm\) \(>\) \(7\) \(cm\)
\(6 + 7 = 13 \) \(cm \) \(>\) \(3\) \(cm\) \(3 +7\)
= \(10\) \(cm\) \(>\) \(6\) \(cm\)
Hence, this triangle is possible.
(iii) Given that, the sides of the triangle are \(6\; cm, 3 \;cm, 2\; cm\).
Here, \(6 + 3 = 9\) \(cm\) \(>\) \(2\) \(cm\)
However, \(3 + 2 = 5\) \(cm\) \(<\) \(6\) \(cm\)
Hence, this triangle is not possible.
Match the items given in Column I with one or more items of Column II.
Column I | Column II |
(a) A plane mirror | (i) Used as a magnifying glass. |
(b) A convex mirror | (ii) Can form image of objects spread over a large area. |
(c) A convex lens | (iii) Used by dentists to see enlarged image of teeth. |
(d) A concave mirror | (iv) The image is always inverted and magnified. |
(e) A concave lens | (v) The image is erect and of the same size as the object. |
- | (vi) The image is erect and smaller in size than the object. |