### Question 17
Related Articles
- \[ s\sqrt{2} = 10\sqrt{2} \]
- \[ s = 10 \]
- \[ s^2 = 10^2 = 100 \, \text{square centimeters} \]
- The sum of the first 10 terms of an arithmetic sequence is 150. If the first term is 5, what is the common difference?
- The sum \( S_n \) of the first \( n \) terms of an arithmetic sequence is given by:
- \[ S_n = \frac{n}{2} (2a + (n-1)d) \]
