We start with this:
x Substitute work y point to plot (x,y)
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-4 y=(-4)²-4 = 16-4 = 12 (-4,12)
-3 y=(-3)²-4 = 9-4 = 5 (-3,5)
-2 y=(-2)²-4 = 4-4 = 0 (-2,0)
-1 y=(-1)²-4 = 1-4 = -3 (-1,-3)
0 y=(0)²-4 = 0-4 = -4 (0,-4)
1 y=(1)²-4 = 1-4 = -3 (1,-3)
2 y=(2)²-4 = 4-4 = 0 (2,0)
3 y=(3)²-4 = 9-4 = 5 (3,5)
4 y=(4)²-4 = 16-4 = 12 (4,12)
Now we plot all those points:
Now we draw a smooth u-shaped graph through those points:
That's it!
Edwin
