Answer: Choice A. 6/7
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Step-by-step explanation:
The given ordered pair is (4, ___) so we have x = 4 here.
We will plug this into f(x) and g(x) to get
f(4) = 6
g(4) = 7
So we have
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If you're curious where f(4) = 6 came from, all we're doing is looking through the set of points
f = {(0, 1), (2, 4), (4, 6), (6, 8)}
to see which has 4 listed first as the x coordinate. That point is (4,6) so x = 4 leads to y = 6, ie, f(x) = 6 when x = 4. A similar situation happens with g(x) as well.