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14Sides AB and AC and median AD of atriangle ABC are respectivelyproportional to sides PQ and PR andmedian PM of another triangle PQR.Show that A ABC - APQR. |
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Answer» mark as best👍💯👍💯👍💯👍💯 Given: Two triangles ΔABC and ΔPQR in which AD and PM are medians such that AB/PQ = AC/PR = AD/PM To Prove: ΔABC ~ ΔPQR Construction: Produce AD to E so that AD = DE. Join CE, Similarly produce PM to N such that PM = MN, also Join RN. Proof: In ΔABD and ΔCDE, we have AD = DE [By Construction] BD = DC [∴ AP is the median] and, ∠ADB = ∠CDE [Vertically opp. angles] ∴ ΔABD≅ΔCDE [By SAS criterion of congruence] ⇒ AB = CE [CPCT] ...(i) Also, in ΔPQM and ΔMNR, we have PM = MN [By Construction] QM = MR [∴ PM is the median] and, ∠PMQ = ∠NMR [Vertically opposite angles] ∴ ΔPQM = ΔMNR [By SAS criterion of congruence] ⇒ PQ = RN [CPCT] ...(ii) Now, AB/PQ = AC/PR = AD/PM ⇒ CE/RN = AC/PR = AD/PM ...[From(i)and(ii)] ⇒ CE/RN = AC/PR = 2AD/2PM ⇒ CE/RN = AC/PR = AE/PN [∴ 2AD = AE and 2PM = PN] ∴ ΔACE ~ ΔPRN [By SSS similarity criterion] Therefore, ∠2 = ∠4 Similarly, ∠1 = ∠3 ∴ ∠1+∠2=∠3+∠4 ⇒ ∠A = ∠P ...(iii) Now, In ΔABC and ΔPQR, we have AB/PQ = AC/PR (Given) ∠A = ∠P [From(iii)] ∴ ΔABC ~ ΔPQR [By SAS similarity criterion] Read more on Brainly.in - https://brainly.in/question/1345163#readmore rational number should be 333 |
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