Erik transformed the equation y = 2(x − 2)^2 + 5 from vertex form to standard form. His steps are shown below. Is Erik's work correct? If not, identify and correct his error.
y = 2(x − 2)^2 + 5
y = 2(x^2 − 4x + 4) + 5
y = 2x^2 − 8x + 8 + 5
y = 2x^2 − 8x + 13
A. No. The error is in the second line: the expanded form of (x − 2)^2 is x^2 − 4.
B. No. The error is in the third line: the product of 2 and x^2 − 4x + 4 is 2x^2 − 4x + 4.
C. No. The error is in the fourth line: the sum of 8 and 5 is 12.
D. Yes. Erik is correct in his transformation from vertex form to standard form.