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Solve the equation: (i) (7x-5)/(8x+3)g...

Solve the equation:
(i) `(7x-5)/(8x+3)gt4`
(ii) `(x)/(x-5)gt(1)/(2)`.

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Let's solve the given inequalities step by step. ### Part (i): Solve the inequality \(\frac{7x - 5}{8x + 3} > 4\) 1. **Rearranging the Inequality**: We start by rewriting the inequality: \[ \frac{7x - 5}{8x + 3} - 4 > 0 \] This can be expressed with a common denominator: \[ \frac{7x - 5 - 4(8x + 3)}{8x + 3} > 0 \] 2. **Simplifying the Numerator**: Now, simplify the numerator: \[ 7x - 5 - 32x - 12 = -25x - 17 \] So, the inequality becomes: \[ \frac{-25x - 17}{8x + 3} > 0 \] 3. **Finding Critical Points**: We need to find the critical points where the numerator and denominator are zero: - For the numerator: \(-25x - 17 = 0 \Rightarrow x = -\frac{17}{25}\) - For the denominator: \(8x + 3 = 0 \Rightarrow x = -\frac{3}{8}\) 4. **Number Line and Test Intervals**: We now plot these critical points on a number line: \[ -\frac{17}{25} \approx -0.68 \quad \text{and} \quad -\frac{3}{8} \approx -0.375 \] The intervals to test are: \((- \infty, -\frac{17}{25})\), \((- \frac{17}{25}, -\frac{3}{8})\), and \((- \frac{3}{8}, \infty)\). 5. **Testing Intervals**: - For \(x < -\frac{17}{25}\) (e.g., \(x = -1\)): \[ \frac{-25(-1) - 17}{8(-1) + 3} = \frac{25 - 17}{-8 + 3} = \frac{8}{-5} < 0 \] - For \(-\frac{17}{25} < x < -\frac{3}{8}\) (e.g., \(x = -0.5\)): \[ \frac{-25(-0.5) - 17}{8(-0.5) + 3} = \frac{12.5 - 17}{-4 + 3} = \frac{-4.5}{-1} > 0 \] - For \(x > -\frac{3}{8}\) (e.g., \(x = 0\)): \[ \frac{-25(0) - 17}{8(0) + 3} = \frac{-17}{3} < 0 \] 6. **Conclusion for Part (i)**: The solution is where the expression is positive: \[ x \in \left(-\frac{17}{25}, -\frac{3}{8}\right) \] ### Part (ii): Solve the inequality \(\frac{x}{x - 5} > \frac{1}{2}\) 1. **Rearranging the Inequality**: Rewrite the inequality: \[ \frac{x}{x - 5} - \frac{1}{2} > 0 \] This can be expressed with a common denominator: \[ \frac{2x - (x - 5)}{2(x - 5)} > 0 \] Simplifying gives: \[ \frac{x + 5}{2(x - 5)} > 0 \] 2. **Finding Critical Points**: We find the critical points where the numerator and denominator are zero: - For the numerator: \(x + 5 = 0 \Rightarrow x = -5\) - For the denominator: \(2(x - 5) = 0 \Rightarrow x = 5\) 3. **Number Line and Test Intervals**: We plot these critical points on a number line: \(-5\) and \(5\). The intervals to test are: \((- \infty, -5)\), \((-5, 5)\), and \((5, \infty)\). 4. **Testing Intervals**: - For \(x < -5\) (e.g., \(x = -6\)): \[ \frac{-6 + 5}{2(-6 - 5)} = \frac{-1}{-22} > 0 \] - For \(-5 < x < 5\) (e.g., \(x = 0\)): \[ \frac{0 + 5}{2(0 - 5)} = \frac{5}{-10} < 0 \] - For \(x > 5\) (e.g., \(x = 6\)): \[ \frac{6 + 5}{2(6 - 5)} = \frac{11}{2} > 0 \] 5. **Conclusion for Part (ii)**: The solution is where the expression is positive: \[ x \in (-\infty, -5) \cup (5, \infty) \] ### Final Answers: 1. For part (i): \(x \in \left(-\frac{17}{25}, -\frac{3}{8}\right)\) 2. For part (ii): \(x \in (-\infty, -5) \cup (5, \infty)\)
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MODERN PUBLICATION-LINEAR INEQUATIONS-EXERCISE 6 (a) Short Answer Type Questions
  1. Solve the equation: (i) 3x-9lt0 (ii) -5x+25le0 (iii) 7x+4gt39 ...

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  2. Solve the equation: (i) x+10gt4x-5 (ii) 8x-2gt5x. (iii) 3x-10gt...

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  3. Solve the equation: (i) x+12lt4x-2. (ii) 4x-7lt3-x.

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  4. Solve the inequation: -(x-3)+4gt-2x+5

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  5. Solve the equation: (i) 3x+17le2(1-x). (ii) -2x+6le5x-4 (iii) 3(...

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  6. Solve the inequalities for real x : 37-(3x+5)geq9x-8(x-3)

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  7. Solve the equation: (i) (x-5)/(x+2)lt0 (ii) (6x-5)/(4x+1)lt0 (ii...

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  8. Solve the following linear inequation in R :(5x-6)/(x+6)<1

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  9. Solve the equation: (i) (7x-5)/(8x+3)gt4 (ii) (x)/(x-5)gt(1)/(2).

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  10. Solve the equation: (i) (3x-2)/(5)le(4x-3)/(2) (ii) (2(x-1))/(5)le...

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  11. Solve the equation: (i) (x-1)/(3)+4lt(x-5)/(5)-2 (ii) (5-2x)/(3)lt...

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  12. Solve the equation: (i) x+(x)/(2)+(x)/(3)lt11 (ii) (x)/(3)gt(x)/(2...

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  13. Solve the equation: (i) (5x)/(2)+(3x)/(4)ge(39)/(4) (ii) (5-2x)/(3...

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  14. Solve the equation: (4+2x)/(3)ge(x)/(2)-3.

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  15. (x)/(4) lt ((5x - 2))/(3) - ((7x - 3))/(5)

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  16. Solve the following linear inequation in R :(2x+3)/5-2<(3(x-2))/5

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  17. Solve the equation: (i) -8le5x-3lt7 (ii) 2le3x-4le5 (iii) -2le4-...

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  18. Solve the equation: (i) -5le(5-3x)/(2)le8 (ii) -15lt(3(x-2))/(5)le...

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  19. Solve the inequalities : 7lt=((3x+11))/2lt=11

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