SOLUTION: Y=-3x-6x-5 I'm experiencing difficulties with figuring out which points to use when creating a table of values. I found that the vertex is (-1,-2) and the y intercept is (0,-5),

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equation Customizable Word Problems -> SOLUTION: Y=-3x-6x-5 I'm experiencing difficulties with figuring out which points to use when creating a table of values. I found that the vertex is (-1,-2) and the y intercept is (0,-5),      Log On


   

Question 533213: Y=-3x-6x-5
I'm experiencing difficulties with figuring out which points to use when creating a table of values. I found that the vertex is (-1,-2) and the y intercept is (0,-5), there is no x intercept. I'm unable to get the graph to open facing downward in an excel spread sheet. I'm not sure if my first point should be my vertex and what other points to use. Please help!
X Y
-1 -2
0 -5
The points that I have are not creating the graph that I need facing downward below the x axis.
Thank you,

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Y=-3x^2-6x-5
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Vertex = ?
x = -b/(2a) = 6/(-6) = -1
f(x) = -3*(-1)^2 -6*-1 -5 = -3+6-5 = -2-
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Vertex is at (-1,-2)
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y- intercept: f(0) = -5
y-intercept at (0,-5)
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Plot those two points and draw a
parabola opening downward.
graph%28400%2C400%2C-10%2C10%2C-10%2C10%2C-3x%5E2-6x-5%29
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Cheers,
Stan H.
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