InterviewSolution
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Solve for x and y, when (√243)x ÷ 3y+1 = 1 and 81(4) – (x/2) – 27y = 01. 3, 42. 5, 43. 2, 44. 4, 3 |
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Answer» Correct Answer - Option 3 : 2, 4 Given∶ (√243)x ÷ 3y+1 = 1, also 81(4) – (x/2) – 27y = 0 Formula Used∶ √a = (a)1/m, (am)n = am × n, am ÷ an = am – n Calculation∶ (√243)x ÷ 3y+1 = 1 {(35)1/2}x ÷ 3y+1 = 1 (35/2)x ÷ 3y+1 = 1 35x/2 ÷ 3y+1 = 1 3(5x/2) – (y + 1) = 30 (5x/2) – (y + 1) = 0 (5x/2) – y – 1 = 0 5x – 2y – 2 = 0 ----(1) Also, 814 – (x/2) – 27y = 0 (34)[4 - (x/2)] – (33)y = 0 316 – (4x/2) – 33y = 0 316 – 2x = 33y 16 – 2x = 3y 2x + 3y – 16 = 0 ----(2) Multiply equation (1) by 3 and equation (2) by 2 15x – 6y – 6 = 0 Or, 15x – 6y = 6 ----(3) 4x + 6y – 32 = 0 ----(4) Add equation (3) and (4) (15x – 6y = 6) + (4x + 6y = 32) ⇒ 19x = 38 ⇒ x = 2 Put x = 2 in equation (1) 5x – 2y – 2 = 0 ⇒ 5(2) – 2y – 2 = 0 ⇒ 10 – 2y – 2 = 0 ⇒ 2y = 8 ⇒ y = 8/2 = 4 ⇒ x = 2, y = 4 ∴ The value of x and y is 2 and 4. |
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