The arithmetic sequence formula provided is given as \( a_n = -8 + (n-1) \cdot 2 \). This formula will allow us to find the y-values (a and b) for the corresponding x-values (2 and 4) in the table.
Let's calculate the values:
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For \( x = 2 \):
- Here, \( n = 2 \).
- Plugging this into the formula: \[ a_2 = -8 + (2 - 1) \cdot 2 = -8 + 1 \cdot 2 = -8 + 2 = -6. \] Thus, \( a = -6 \).
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For \( x = 4 \):
- Here, \( n = 4 \).
- Plugging this into the formula: \[ a_4 = -8 + (4 - 1) \cdot 2 = -8 + 3 \cdot 2 = -8 + 6 = -2. \] Thus, \( b = -2 \).
So the values are:
- \( a = -6 \)
- \( b = -2 \)
The correct response is: a = -6; b = -2.