1. **State the problem:** We need to determine which of the given compound inequalities has no solution.
2. **Recall:** A compound inequality joined by "and" means the solution must satisfy both inequalities simultaneously.
3. **Analyze each compound inequality:**
**(a) Solve** $7x - 8 > 9(x - 1)$ and $3x + 2 < 5x + 3$
- First inequality:
$$7x - 8 > 9x - 9$$
$$7x - 8 - 9x + 9 > 0$$
$$-2x + 1 > 0$$
$$-2x > -1$$
$$\cancel{-2}x > \cancel{-1}$$
$$x < \frac{1}{2}$$ (note the inequality flips because we divided by a negative)
- Second inequality:
$$3x + 2 < 5x + 3$$
$$3x + 2 - 5x - 3 < 0$$
$$-2x - 1 < 0$$
$$-2x < 1$$
$$x > -\frac{1}{2}$$
- Combined solution:
$$-\frac{1}{2} < x < \frac{1}{2}$$ (non-empty solution set)
**(b) Solve** $-2x + 5 < -3x - 3$ and $-4x + 9 \geq -5x + 2$
- First inequality:
$$-2x + 5 < -3x - 3$$
$$-2x + 5 + 3x + 3 < 0$$
$$x + 8 < 0$$
$$x < -8$$
- Second inequality:
$$-4x + 9 \geq -5x + 2$$
$$-4x + 9 + 5x - 2 \geq 0$$
$$x + 7 \geq 0$$
$$x \geq -7$$
- Combined solution:
$$x < -8$$ and $$x \geq -7$$
- These two conditions cannot be true simultaneously, so **no solution**.
**(c) Solve** $3(x - 1) > 4(x - 2)$ and $2(x + 2) \leq 5(x - 1)$
- First inequality:
$$3x - 3 > 4x - 8$$
$$3x - 3 - 4x + 8 > 0$$
$$-x + 5 > 0$$
$$-x > -5$$
$$x < 5$$
- Second inequality:
$$2x + 4 \leq 5x - 5$$
$$2x + 4 - 5x + 5 \leq 0$$
$$-3x + 9 \leq 0$$
$$-3x \leq -9$$
$$x \geq 3$$
- Combined solution:
$$3 \leq x < 5$$ (non-empty solution set)
**(d) Solve** $-2x + 5 \geq -3x - 2$ and $-3x - 2 > -2x + 4$
- First inequality:
$$-2x + 5 \geq -3x - 2$$
$$-2x + 5 + 3x + 2 \geq 0$$
$$x + 7 \geq 0$$
$$x \geq -7$$
- Second inequality:
$$-3x - 2 > -2x + 4$$
$$-3x - 2 + 2x - 4 > 0$$
$$-x - 6 > 0$$
$$-x > 6$$
$$x < -6$$
- Combined solution:
$$x \geq -7$$ and $$x < -6$$
- This is the interval $$[-7, -6)$$ which is non-empty.
4. **Conclusion:** The only compound inequality with no solution is option (b).
**Final answer:** The compound inequality $$-2x + 5 < -3x - 3$$ and $$-4x + 9 \geq -5x + 2$$ has no solution.
Compound Inequalities 343E25
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