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Absolute value graphs (1 Viewer)

Zuroy

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What is the "quick" (faster) method of sketching absolute value graphs rather than doing the old 'table of values' method?

For example: Graph y = | x + 2 |
Should i just draw the graph of y = x + 2 but stop the line when it reaches 0 on the x-axis and then draw a reflection of that on the other side?

And for the question: y = 3x (without using a table of values since thats a bit slow)
How do i get the intercepts to plot of the graph when:
let x = 0 then y = 0
let y = 0 then x = 0
Some people are telling me to just memorize the shape of the graph but isnt that a little bit silly?



 

SeCKSiiMiNh

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What is the "quick" (faster) method of sketching absolute value graphs rather than doing the old 'table of values' method?

For example: Graph y = | x + 2 |
Should i just draw the graph of y = x + 2 but stop the line when it reaches 0 on the x-axis and then draw a reflection of that on the other side?

And for the question: y = 3x (without using a table of values since thats a bit slow)
How do i get the intercepts to plot of the graph when:
let x = 0 then y = 0
let y = 0 then x = 0
Some people are telling me to just memorize the shape of the graph but isnt that a little bit silly?



i would draw the complete y= x+2 then rub out any parts under the x axis and draw the reflection of it. it's the fastest way imo.

and for the y= 3x thing, (0,0) is a point on the graph, yes. then let y =1, so x = 1/3 and connect the dots. basically, its like the y=x graph, but the slope is steeper.
 

mOusaa

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no its not silly they are simple and you should memorise them to save time for example y=l x+2 l is the same as y=l x l moved two units to the left and intercepts the y axis at y=2
 

Lukybear

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If its stright, just memorise. Then translate via movement left or right, up or down.

If its curve, then draw and reflect.
 

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