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The first three steps in writing f(x) = 40x + 5x2 in vertex form are shown.
Write the function in standard form. f(x) = 5x² + 40x
Factor a out of the first two terms. f(x) = 5(x2 + 8x)
Form a perfect square trinomial.
* = 16
f(x) = 5(x2 + 8x + 16) - 5(16)
What is the function written in vertex form?
f(x) = 5(x + 4) - 80
f(x) = 5(X + 8) - 80
f(x) = 5(x + 4)2 – 80
f(x) = 5(X + 8)2 - 80