To determine which function has a constant additive rate of change of –1/4, we should look at each option and calculate the slope or rate of change.
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Straight line with a negative slope: A straight line will have a constant rate of change. We can calculate the slope using the two points provided, (−2, 2) and (2, 1): \[ \text{slope} = \frac{y_2 - y_1}{x_2 - x_1} = \frac{1 - 2}{2 - (-2)} = \frac{-1}{4} \] This line has a constant rate of change of –1/4.
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Curved line: This is less likely to have a constant additive rate of change since it is not a straight line. The points provided do not indicate a consistent additive change like a linear function would.
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First table:
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For \( x = 20 \) to \( x = 21 \), \( y = -1 \) to \( y = -1.5 \): \[ \Delta y = -1.5 - (-1) = -0.5 \quad \text{for} \quad \Delta x = 1 \] Slope = \(-0.5/1 = -0.5\)
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For \( x = 21 \) to \( x = 22 \), \( y = -1.5 \) to \( y = -2 \): \[ \Delta y = -2 - (-1.5) = -0.5 \] Slope = \(-0.5/1 = -0.5\)
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Similar calculation will give the same slope for the other rows. The additive rate of change is consistently –0.5.
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Second table:
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For \( x = -12 \) to \( x = -11 \), \( y = 7 \) to \( y = 11 \): \[ \Delta y = 11 - 7 = 4 \quad \text{for} \quad \Delta x = 1 \] Slope = \(4/1 = 4\)
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For \( x = -11 \) to \( x = -10 \), \( y = 11 \) to \( y = 14 \): \[ \Delta y = 14 - 11 = 3 \] Slope = \(3/1 = 3\)
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Again, similar calculations show that this table has a positive additive rate of change.
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In summary, the function that has a constant additive rate of change of -1/4 is the first option, the straight line with a negative slope.