How do you graph the parabola y=2x2+4 using vertex, intercepts and additional points?

1 Answer
May 13, 2018

Refer explanation section

Explanation:

Given -

y=2x2+4

To find the vertex, rewrite the function as

y=2x2+0x+4

x-coordinate of the vertex

x=b2a=02×2=0

y coordinate of the vertex

At x=0; y=2(0)2+0(0)+4=4

Vertex (0,4)

y Intercept (0,4)

To find the x-intercept put y=0

2x2+4=0
2x2=4
x2=42
x=±42 [The function has imaginary roots. It means, it doesn't have x-intercept.

Take a few points on either side of x=0. Frame a table -

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Plot the points on a graph sheet. Join them with a smooth curve.
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