How do you identify the important parts of y=−4x2 to graph it?

1 Answer
Sridhar V.
Aug 3, 2018


Please read the explanation.

Explanation:


Vertex-Form of a Quadratic Equation:

y=f(x)=a(x−h)2+k, where

(h,k) is the Vertex

y=f(x)=x2

is the parent function

We can see that a=1;h=0,k=0

Vertex (0,0)

Axis of Symmetry is at (x=0)

Since a>0, the parabola opens up.

For the given function:

y=f(x)=−4x2

a=−4,h=0,k−0

The value of a,(a<0), the parabola opens down.

Vertex is at (0,0)

Axis of Symmetry is at (x=0)

Make a data table for the parent function

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Make a data table for the given function

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Draw the graphs for both of them and analyze the behavior of the quadratic functions:

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The graph of the given function

y=f(x)=−4x2

is compressed horizontally since a=−4

Hope this is helpful;.

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