Proving using RHS Congruency Test

Proving using RHS Congruency Test

Secondary 3

In the diagram, \(PQR\) and \(QST\) are straight lines.

It is given that \(TQ\) is perpendicular to \(PR\), \(PT=SR\), \(QR=2QS\), where \(S\) is the midpoint of \(QT\) and \(\angle QRS=28{}^\circ\).

  1. Identify a pair of congruent triangles and state the reason for their congruence.
  2. If the length of \(QS\) is \(20\) units, find the ratio \(PQ:QR\).

Source check: in right triangle \(QRS\), \(QR=2QS\) implies \(\tan\angle QRS=1/2\), so the angle is approximately \(26.6^\circ\), not the printed \(28^\circ\). The requested congruence proof and ratio use the side conditions and do not require that inconsistent angle.

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Answer:\(\text{(i)}\ \triangle TQP\equiv\triangle RQS\text{ (RHS)}\) \(\text{(ii)}\ PQ:QR=1:2\) Results are conditional as explained in the source check; the complete printed givens are inconsistent.

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