77. In Fig. PT and PS are tangents to a circle from a point P such tha

1.	77. In Fig. PT and PS are tangents to a circle from a point P such that PT-5 cm andTPS60". Find the length of chord TS.
Answer» PS=PT. ( when two tangents met at a point externally then their lenghts are equal) therefore angle PTS= angle PST. (angle opposite to equal sides are equal) now in triangle PTS Angle PTS +Angle PST +Angle TPS=180 <PTS+<PTS+60=180 2<PTS=180-60 <PTS =60<PSt =60 therefore all angles are 60 degree it means it is an equilateral triangle and we know that sides of equilateral triangle are equal so the chord TS is of 5cm

77. In Fig. PT and PS are tangents to a circle from a point P such that PT-5 cm andTPS60". Find the length of chord TS.

Answer»

PS=PT. ( when two tangents met at a point externally then their lenghts are equal)

therefore

angle PTS= angle PST. (angle opposite to equal sides are equal)

now in triangle PTS

Angle PTS +Angle PST +Angle TPS=180

<PTS+<PTS+60=180

2<PTS=180-60

<PTS =60<PSt =60

therefore all angles are 60 degree it means it is an equilateral triangle

and we know that sides of equilateral triangle are equal

so the chord TS is of 5cm