Answer:
QS = 20
Step-by-step explanation:
Since TS is parallel to PR and intersects the other 2 sides then it divides those sides proportionally, that is
[tex]\frac{QT}{TP}[/tex] = [tex]\frac{QS}{SR}[/tex], substitute values
[tex]\frac{25}{15}[/tex] = [tex]\frac{QS}{12}[/tex] ( cross- multiply )
15QS = 300 ( divide both sides by 15 )
QS = 20
