If you have y=-2 then you simply replace y with -2 and evaluate x. So for instance
let y=-2
plug in y=-2
Add 4 to both sides
So if y=-2, then We do the same for every y that is in the table
We're basically going backwards. Instead of finding y with the given x values, we find x with the give y values. So to do this efficiently, we need to solve for x:
Add 4 to both sides
Divide both sides by 5 to solve for x.
Now if we evaluate each y we get:
plug in y=-2
So if y=-2, x=2/5
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plug in y=-1
So if y=-1, x=3/5
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plug in y=0
So if y=0, x=4/5
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plug in y=1
So if y=1, x=1
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plug in y=2
So if y=2, x=6/5
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So here's the table filled out:
x y
2/5 | -2
3/5 | -1
4/5 | 0
1 | 1
6/5 | 2