SOLUTION: y+4x^2=0 decide wheter the graph of the equation opens up or down. then find the coordinates of the vertex

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Question 422555: y+4x^2=0
decide wheter the graph of the equation opens up or down. then find the coordinates of the vertex
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
y%2B4x%5E2=0

y=+-4x%5E2........compare with the general quadratic equation
y+=+ax%5E2+%2B+bx+%2B+c
Here, a+=+-4+, b+=0, and c+=+0
Substitute a+=+-4+ and b+=0 in the equation of axis of symmetry,
x=+-b%2F2a
x=-0%2F2%28-4%29
x=0

so, the equation of the axis of symmetry for this parabola is x+=+0
Since the equation for the axis of symmetry is x+=+0%7D%7D+and+the+%7B%7B%7Bvertex lies on the axis, the x%96coordinate for the vertex is 0.
Substitute x+=+0 in the given equation y=+-4x%5E2
y=+-4%2A0%5E2
y+=+0
The coordinates of vertex are (0, 0).
The coefficient of x%5E2 is negative, therefore the vertex is a maximum and
the graph of the equation opens down.
+graph%28+500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C+-4x%5E2%29+