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प्रश्न
M and N are points on the sides PQ and PR respectively of a ΔPQR. For the following case, state whether MN || QR
PM = 4cm, QM = 4.5 cm, PN = 4 cm and NR = 4.5 cm
उत्तर
We have, PM = 4cm, QM = 4.5 cm, PN = 4 cm and NR = 4.5 cm
Hence,
`"PM"/"QM"=4/4.5=8/9`
Also,
`"PN"/"NR"=4/4.5=8/9`
Hence, `"PM"/"QM"="PN"/"NR"`
By converse of proportionality theorem
MN || QR
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