Q4 of 59 Page 82

In figure 3.80, if PQ = 6, QR = 10, PS = 8 find TS.


Given: PQ = 6, QR = 10, PS = 8


PT × PS = PR × PQ


This property is known as theorem of chords intersecting outside the circle.


⇒ PR = PQ + RQ = 6 + 10 = 16


⇒ PT × 8 = 16 × 6


⇒ PT = 12


TS = PT – PS = 12 – 8 = 4


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