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Question
In ΔABC, PQ || BC. If PB = 6 cm, AP = 4 cm, AQ = 8 cm, find the length of AC.
Options
12 cm
20 cm
6 cm
14 cm
Solution
20 cm
Explanation:
In ΔABC, PQ || BC
∴ `("AP")/("PB") = ("AQ")/("QC")` ...(By proportionality theorem)
`\implies 4/6 = 8/("QC")`
`\implies` QC = `(8 xx 6)/4` = 12 cm
Now, AC = AQ + QC
= 8 + 12
= 20 cm.
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