SOLUTION: what is the vertex and x-intercepts of y = x^2 + 4x + 7

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Question 316527: what is the vertex and x-intercepts of y = x^2 + 4x + 7
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Complete the square to get to vertex form.
y=a%28x-h%29%5E2%2Bk
where (h,k) is the vertex.
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x%5E2+%2B+4x+%2B+7=%28x%5E2%2B4x%2B4%29%2B3
x%5E2+%2B+4x+%2B+7=%28x%2B2%29%5E2%2B3
The vertex is (-2,3)
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Now set the equation equal to zero to solve for the zeros.
%28x%2B2%29%5E2%2B3=0
%28x%2B2%29%5E2=-3
x%2B2=0+%2B-+sqrt%283%29i
x=-2+%2B-+sqrt%283%29i where i=sqrt%28-1%29