Answer:
-1
Explanation:
We are given:
a₁ = -17
a₁₃ = -29
Solving for the Common Difference (d):
We know that the formula for an AP is:
aₙ = a₁ + (n-1)d
The formula for the third term will be:
a₁₃ = a₁ + (13 - 1)d
replacing the given values:
-29 = -17 + (12)d
-12 = 12d [adding 17 on both sides]
d = -1 [dividing both sides by 12]
Hence, the common difference is -1