Answer: D. {-12, -9, -6, -3, 0}
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Explanation:
The domain is the set of allowed x inputs. The range is the set of possible y outputs.
The set {-2,-1,0,1,2} represents all the possible x inputs
Let's plug each of those into the equation y = 3x-6 to find the corresponding paired out puts.
Note: y = f(x), so f(x) = 3x-6 is the same as y = 3x-6.
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If x = -2, then,
y = 3x-6
y = 3(-2)-6
y = -6-6
y = -12
We see that x = -2 and y = -12 pair up together.
The value -2 in the domain maps to -12 in the range.
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If x = -1, then,
y = 3x-6
y = 3(-1)-6
y = -3-6
y = -9
The input x = -1 in the domain maps to the output y = -9 in the range
So far the range consists of {-12, -9} in either order.
The answer is between A and D
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If x = 0, then,
y = 3x-6
y = 3(0)-6
y = 0-6
y = -6
So -6 is also part of the range. We have {-12, -9, -6} so far. The answer is still between A and D.
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If x = 1, then,
y = 3x-6
y = 3(1)-6
y = 3-6
y = -3
The range updates to {-12, -9, -6, -3}
A and D are still equally valid
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We have one more x value to try
If x = 2, then,
y = 3x-6
y = 3(2)-6
y = 6-6
y = 0
Since y = 0 is in the range, instead of y = 1, this rules out choice A
The answer is therefore D. {-12, -9, -6, -3, 0}
