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Solve for x and y:\(\frac{44}{x+y}+\frac{30}{x-y}=10\),\(\frac{55}{x+y}-\frac{40}{x-y}=13\) |
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Answer» The given equations are \(\frac{44}{x+y}+\frac{30}{x-y}=10\)............(i) \(\frac{55}{x+y}-\frac{40}{x-y}=13\)..........(ii) Putting 1/x+y = u and 1/x−y = v, we get: 44u + 30v = 10 ……..(iii) 55u + 40v = 13 …….(iv) On multiplying (iii) by 4 and (iv) by 3, we get: 176u + 120v = 40 …..(v) 165u + 120v = 39 …..(vi) On subtracting (vi) and (v), we get: 11u = 1 ⇒u = 1/11 ⇒ 1/x+y = 1/11 ⇒ x + y = 11 …….(vii) On substituting u = 1/11 in (iii), we get: 4 + 30v = 10 ⇒30v = 6 ⇒v = 6/30 = 1/5 ⇒ 1/x−y = 1/5 ⇒ x – y = 5 …….(viii) On adding (vii) and (viii), we get 2x = 16 ⇒ x = 8 On substituting x =8 in (vii), we get: 8 + y = 11 ⇒ y = 11 – 8 = 3 Hence, the required solution is x = 8 and y = 3. |
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