How do you graph y=|2x+3|y=|2x+3|?

1 Answer
Jul 27, 2018

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Please read the explanation.

Explanation:

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We are given the absolute value function:

color(red)(y=f(x)=|2x+3|y=f(x)=|2x+3|

The color(blue)("General Form of an Absolute Value Function"General Form of an absolute Value Function:

color(green)(y=f(x)=a|mx-h|+ky=f(x)=a|mxh|+k, where

color(green)(a, m, h, k in RR

Vertex: color(blue)(((h)/m,k)

Axis of Symmetry: color(blue)(x=(h)/m

We are given

color(red)(y=f(x)=|2x+3|

a=1; m=2; h=-3 and k = 0

Note that h=(-3), since the formula contains (-h)

Vertex : color(red)(((-3)/2, 0)

Hence, Vertex is color(red)((-1.5, 0)

Axis of Symmetry : color(red)(((-3)/2)

Hence, Axis of Symmetry is at color(red)(x=(-1.5)

Create a data table for the Parent Function

y = f(x)=|x| and

the given absolute value function

y = f(x)=|2x+3|

The data table is given below:

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Draw the graph for color(red)(y=f(x)=|x|

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Draw the graph for color(red)(y=f(x)=|2x+3|

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Observe that,

Vertex :color(red)((-1.5,0)

Draw the Axis of Symmetry on the graph as shown below:

enter image source here

Keep both the graphs of

color(blue)(y=f(x)=|x| and

color(blue)(y=f(x)=|2x+3|

as shown below and analyze the transformations:

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Observe that the values color(blue)(a, m, h and k influence the corresponding transformations.

All transformations are with reference to the parent graph.

color(red)((h) is responsible for a horizontal transformation.

color(red)[[h=(-3)] indicates that the graph shifts horizontally by 3 units to the left.

Hope you find this solution helpful.