MATHEMATICS · Multi-part · CBSE · Mathematics · Lines and Angles · Lines and Angles
Problem
Four different situations are described below. For each situation, classify the named pair of angles as (a) adjacent but not linear pair, (b) linear pair, (c) complementary but not adjacent, (d) supplementary but not adjacent, or (e) vertically opposite. Give one geometrical reason for every answer.
(i) Two right angles share a common vertex and one common arm; their non-common arms are opposite rays.
(ii) Two acute angles form a pair whose arms do not meet except at the common vertex and whose sum is 90∘.
(iii) Two obtuse angles are opposite angles formed by the intersection of two straight lines.
(iv) An acute angle and an obtuse angle have the same vertex, share no common arm, and their sum is 180∘.