Find the value of the unknown exterior angle x in the following diagrams:
(i) \(x = 50° + 70°\) (Exterior angle theorem)
\(x\) = \(120°\)
(ii) \(x = 65° + 45°\) (Exterior angle theorem)
= \(110°\)
(iii) \(x = 40° + 30°\) (Exterior angle theorem)
= \(70°\)
(iv) \(x = 60° + 60°\) (Exterior angle theorem)
= \(120°\)
(v) \(x = 50° + 50°\) (Exterior angle theorem)
= \(100°\)
(vi) \(x = 30° + 60°\) (Exterior angle theorem)
= \(90°\)
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. |