If lines AB and CD are parallel, find the measure of angle x.
[3 Marks]
Given, AB is parallel to CD.
Therefore, ∠EGC=180∘−(2x+3x) (Angles in linear pair) [1 Mark]
Also, ∠EGC=∠AFG=75∘ (Corresponding angles) [1 Mark]
⇒180∘−(2x+3x)=75∘
⇒−5x=75∘−180∘
⇒5x=105∘
⇒x=21∘ [1 Mark]