Final answer:
The 17th partial sum (S17) for the arithmetic sequence with a first term of 7 and a common difference of 9 is 1343, calculated using the formula for the sum of an arithmetic series.
Step-by-step explanation:
The student is asked to find the 17th partial sum (S17) of an arithmetic sequence with the first term (a) being 7 and the common difference (d) being 9. To find S17, we can use the formula for the sum of an arithmetic series: Sn = (n/2) * (2a + (n - 1)d), where n is the number of terms, a is the first term, and d is the common difference between the terms.
Using the formula, we get:
S17 = (17/2) * (2*7 + (17 - 1)*9)
S17 = (17/2) * (14 + 16*9)
S17 = (17/2) * (14 + 144)
S17 = (17/2) * 158
S17 = 17 * 79
S17 = 1343.
Therefore, the 17th partial sum of the arithmetic sequence is 1343.