Which of the following functions best describes this graph
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Answer: Choice C)
y = (x-2)(x-2)
note: This is the same as y = (x-2)^2
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The x intercept or root is x = 2, so x-2 is a factor. There is only one root visible, but this is a parabola, so it's technically a double root (it repeats itself). That is why (x-2) shows up twice giving (x-2)(x-2)
If the equation was simply y = x-2, then it would be a linear equation instead of a curved parabola.
Note how plugging in x = 2 leads to the following y value
y = (x-2)(x-2)
y = (2-2)*(2-2)
y = 0*0
y = 0
So (2,0) is the only x intercept.