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Using the completing-the-square method, rewrite f(x) = x2 − 8x + 3 in vertex form.

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The vertex-form of a quadratic equation is
f(x)=a(x-h)^(2)+k, where (h, k) is the vertex of the parabola.

To complete the square of a quadratic expression in standard form, we write the coefficient of x as 2*b, then add and subtract
b^(2).


f(x)= x^(2) -8x+3


f(x)= x^(2) -2*4x+3

so b=4, now add and subtract
4^(2).


f(x)= x^(2) -2*4x+ 4^(2)- 4^(2)+3


f(x)=( x^(2) -2*4x+ 4^(2))- 16+3


f(x)=(x-4)^(2)-13
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