Respuesta :

caylus
Hello,
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Answer B
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2x²+28x-5=2(x²+2*7x+49)-5-2*48
=2(x+7)²-103

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Answer:

[tex]f(x)=2(x+7)^2-103[/tex]

Step-by-step explanation:

[tex]f(x) = 2x^2+28x - 5[/tex]

To find out vertex apply the formula x=-b/2a

The value of a=2 and b=28

[tex]x=\frac{-b}{2a} =\frac{-28}{4} =-7[/tex]

Now plug in x=-7 in f(x) equation and find out f(-7)

[tex]f(-7) = 2(-7)^2+28(-7)- 5=-103[/tex]

Vertex is (-7,-103)

Now use vertex formula

[tex]f(x)=a(x-h)^2+k[/tex]

a=2, h=-7, k=-103

Plug in all the values in the vertex form equation

[tex]f(x)=2(x+7)^2-103[/tex]