Arithmetic Sequence Lesson 11-2

The explicit formula for the nth term of an arithmetic sequence is a_n = a₁ + d(n - 1).  What does each variable in the explicit formula represent?

• a_n is the nth term, a₁ is the first term, d is the number of dogs and n is the number nurses
• a_n is the nth term, a₁ is the first term, d is the difference between the x terms,and n is the term number
• a_n is the nth term, a₁ is the first term, d is the difference between the y terms, and n is the term number
• a_n is the nth term, a₁ is the first term, d is the difference between both the x and y terms, and n is the number term

What is a₅₀ of the arithmetic sequence 45, 40, 35, 30, ...?

• 95
• -200
• -20
• 80

The 8th term of an arithmetic sequence is 12.5 and the 13th term is 20.  What is a₂₅?

• 38
• 32.5
• 45
• 7.5

Could an arithmetic sequence also be a direct variation?

• No, a direct variation always contains the point (1, 1) and this does not make sense for an arithmetic sequence because there can be no first term
• No, a direct variation always contains the point (0, 0) and this does not make sense for an arithmetic sequence because there can be no zero term
• No, a direct variation always contains the point (2, 2) and this does not make sense for an arithmetic sequence because there can be no second term
• No, a direct variation always contains the point (3, 3) and this does not make sense for an arithmetic sequence because there can be no third term

Why is the graph of an arithmetic sequence made up of discrete points?

• The x-values represent individual terms of the sequence and the y-values represent term numbers (which must be whole numbers)
• The x and y values represent ordered pairs on a graph and all graphs are discrete
• The x-values represent the values of the range and y-values represent the values of the domain
• The x-values represent term numbers (which must be whole numbers as they are the n =) and the y-values represent individual terms of the sequence