Answer:
B
Explanation:
let y = f(x) and rearrange making x the subject
y = (2x - 4)² ( take the square root of both sides )
= 2x - 4 ( add 4 to both sides )
+ 4 = 2x ( divide terms on both sides by 2 )
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+ 2 = x
x =
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+ 2
Change y back into terms of x
(x) =
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+ 2, x ≥ 0