How do you graph the parabola y= (x + 3)^2 - 2y=(x+3)22 using vertex, intercepts and additional points?

1 Answer
Jul 10, 2016

Refer explanation section

Explanation:

The given quadratic equation is in the vertex form

y=(x-3)^2-2y=(x3)22

Hence the vertex is (3, -2)(3,2)

(3, -2)(3,2)This is one of the points on the curve.

x=-3x=3 is the minimum point on the curve. Hence to graph the curve, we take two point to the left of x=3x=3 and two point to its right.

Right side points -

At x=5; y=(5-3)^2-2=4-2=2x=5;y=(53)22=42=2

(5,2)(5,2)

At x=4; y=(4-3)^2-2=1-2=-1x=4;y=(43)22=12=1

(-4,-1)(4,1)

(3, -2)(3,2)

Left side points.

At x=2; y=(2-3)^2-2=1-2=-1x=2;y=(23)22=12=1

(-2, -1)(2,1)

At x=1; y=(1-3)^2-2=4-2=2x=1;y=(13)22=42=2

(-1,2)(1,2)

Plot the points
(5, 2), (4, -1), (3, -2), (2, 1), (-1, 2)(5,2),(4,1),(3,2),(2,1),(1,2)

Table developed in Excel for the equation y=(x-3)^2-2y=(x3)22

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You will get the graph.

Graph developed in Excel

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