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प्रश्न
E and F are points on the sides PQ and PR, respectively, of a ΔPQR. For the following case, state whether EF || QR.
PQ = 1.28 cm, PR = 2.56 cm, PE = 0.18 cm and PF = 0.36 cm
उत्तर
PQ = 1.28 cm, PR = 2.56 cm, PE = 0.18 cm, PF = 0.36 cm
`("PE")/("PQ") = 0.18/1.28 = 18/128 = 9/64`
`("PF")/("PR") = 0.36/2.56=9/64`
Hence, `("PE")/("PQ") = ("PF")/("PR")`
Therefore EF is parallel to QR.
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