What is the vertex of $y = x^{2} + 4 x + 1$ $y= x^2+4x + 1$ ?

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Answer 1 · 2015-11-26T15:58:44

$P_{vertex} = (- 2, - 3)$ $P_("vertex")=(-2,-3)$

Given: $color(brown)(y=x^2+4x+1) ............................(1)$

Let point of vertex be $P_("vertex")$

Extract the 4 from $4x$

Do the following to it:

$-1/2xx4=-2$

$x_("vertex")=color(blue)(-2)............................(2)$
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Substitute (2) into equation (1) to find $y_("vertex")$

$color(brown)(y_("vertex")=color(blue)((-2))^2+4color(blue)((-2))+1)$

$y_("vertex")= 4-8+1 =-3$
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Tont B

What is the vertex of y= x^2+4x + 1 y=x2+4x+1y= x^2+4x + 1 ?