Question 76279:  I really need some help with this. Please. Find the axis of symmetry. 
Y = x^2 + 5x -9
 
Thanks 
 Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! Find the axis of symmetry. 
Y = x^2 + 5x -9  
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There are at least two ways to do this: 
1st: Find the x-value of the max point at x=-b/2a 
x=-5/2 
That is the axis of symmetry. 
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2nd: Put in vertex form: 
y+9 = x^2+5x 
Complete the square to get: 
x^2+5x+(5/2)^2 = y+9+(5/2)^2 
Factor to get: 
(x+(5/2))^2 = y+(61/4) 
This tells you the vertex is at ((-5/2),(-61,4)) 
Axis of symmetry is x=-5/2 
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Cheers, 
Stan H. 
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