WAEC 2019 · Paper 1 · Q44

In the same diagram ( $PQ \parallel RS$ , $\angle QFG = 105^\circ$ , $\angle FEG = 50^\circ$ ), find the value of $n$ .

Worked solution (try it first)

$PQ \parallel RS$ , so $\angle QFG$ and $\angle FGS$ are co-interior: $\angle FGS = 180^\circ - 105^\circ$
$= 75^\circ$ .
$n$ is vertically opposite $\angle FGS$ , so $n = 75^\circ$ , option C.