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Question
E and F are points on the sides PQ and PR, respectively, of a ΔPQR. For the following case, state whether EF || QR:
PE = 4 cm, QE = 4.5 cm, PF = 8 cm and RF = 9 cm
Solution
PE = 4 cm, QE = 4.5 cm, PF = 8 cm, RF = 9 cm
`("PE")/("EQ") = 4/4.5 = 40/45 = 8/9`
`("PF")/("FR") = 8/9`
`("PF")/("FR")=("PE")/("EQ")`
Therefore, EF is parallel to QR.
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