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Question 10 of 32
1 Point
The standard form of the equation of a parabola is
y=1x2 - 4x +21. What is the vertex form of the equation?
O A. y =(x+4)2 +13
O B. y=2(x+4)2 +21
C. y = 2(x-4)2 + 21
D. y = -(x-4)? +13