Question

(a) What are the three conditions that must be satisfied for two angles to be adjacent? [3 MARKS]

(b) In the given figure, $\angle 1$ and $\angle 2$ are supplementary angles. If $\angle 1$ decreases, then $\angle 2$ will _______ so that both the angles are still supplementary.

Answer 1

(a) Conditions: 2 Marks
(b) Explanation: 1 Mark

(a) Two angles are said to be adjacent if they have:

i) Common vertex

ii) Common arm

iii) Non-common arms are on either side of the common arm

(b) If $\angle 1$ decreases then, $\angle 2$ will increase by the same measure, so that both the angles are still supplementary.