What is the vertex of the parabola y=(x+8)^2+1?

1 Answer
Mar 8, 2016

color(blue)(x_("vertex")=-8)
I have taken you up to appoint where you should be able to finish it off.

Explanation:

Standard form y=ax^2+bx+c

Write as:" "y=a(x^2 +b/ax) +c

Then x_("vertex")=(-1/2)xxb/a

Expanding the brackets

y=x^2+16x +84+1

In your case a=1" so "b/a =16/1

Apply (-1/2)xx16= -8

color(blue)(x_("vertex")=-8)

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Find y_("vertex")" " by substitution

color(brown)(y=x^2+16x +85)color(green)( -> y=(-8)^2+16(-8) +85)

I will let you finish this bit

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Tony B