TRUE. The common difference in an arithmetic sequence can be positive, negative, or even zero. A negative common difference means each term is smaller than the previous term—the sequence is decreasing. Example: 20, 15, 10, 5, 0, -5, ... Here, d = 15 - 20 = -5 (negative). Each term decreases by 5. Example with d = 0: 7, 7, 7, 7, ... (constant sequence). All formulas work the same way regardless of whether d is positive or negative. For instance, if a = 20, d = -5, n = 6: \(T_6 = 20 + (6-1)(-5) = 20 + 5(-5) = 20 - 25 = -5\) ✓. In ECZ examinations, questions with negative common differences test whether students truly understand the concepts rather than just memorizing patterns. Don't be confused when d is negative—the formula remains exactly the same. Negative d appears in real-world contexts like depreciation, temperature decreases, or descending patterns.

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• ivwananji siwale – 29 pts

• Distance of A Straight Line
• Mid-point of A Line
• Equation of a Straight Line
• Parallel and Perpendicular Lines
• COMMUNICATION SYSTEMS