. What is the common difference?
The common difference is 8.
The common difference is 8.
a+11d=72
subtract
7d = 49
d = 49/7
the bot was wrong
The formula for the nth term of an arithmetic sequence is given by:
aₙ = a₁ + (n-1)d
where:
aₙ is the nth term,
a₁ is the first term,
n is the position of the term,
d is the common difference.
To find the common difference (d), we can use the given information.
Step 1: Substitute the values into the formula for both the fifth term and the twelfth term:
a₅ = a₁ + (5-1)d
23 = a₁ + 4d
a₁₂ = a₁ + (12-1)d
72 = a₁ + 11d
Step 2: Solve the system of equations formed by the two equations.
From equation (1), we can rearrange it to get:
a₁ = 23 - 4d (equation 3)
Substitute equation (3) into equation (2):
72 = (23 - 4d) + 11d
Simplifying the equation:
72 = 23 + 7d
49 = 7d
d = 49/7 = 7
Therefore, the common difference (d) of the arithmetic sequence is 7.
To find the first term (a₁), substitute the value of d into equation (3):
a₁ = 23 - 4(7)
a₁ = 23 - 28
a₁ = -5
So, the first term (a₁) of the sequence is -5, and the common difference (d) is 7.