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Diagonals of a rhombus BEST intersect at A.(i) If m∠BTS = 110°, then find m∠TBS(ii) If l(TE) = 24, l(BS) = 70, then find l(TS)= ? |
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Answer» (i) now, ∆TBS , BT = TS so, ∠TBS = ∠TSB ------(1) Given, ∠BTS = 110° we KNOW, sum of all angles of triangle is 180° so, ∠BTS + ∠TBS + ∠TSB = 180° => 110° + 2(∠TBS) = 180° [ from equation (1)] =>2(∠TBS) = 180° - 110° = 70° => ∠TBS = 35° hence, ∠TBS = 35° (ii) Given, length of TE = 24 length of BS = 70 we know, diagonals of rhombus are perpendicular bisector to each other. so, BA = AS = BS/2 = 35 similarly, TA = AE = TE/2 = 12 now, ∆ATS is right - angled triangle. from Pythagorean theorem, TS² = TA² + AS² = 35² + 12² = 1225 + 144 = 1369 TS = TS = 37 |
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