Question

How do you find the inverse of `2x-3y= -15`?

Answer 1

`color(blue)(=>y=3/2x-15/2)`

Explanation:

Given:`" "2x-3y=-15`

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Note that the given equation `-> y=2/3x+5` ...............(1)
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Add `3y` to both sides

`2x+3y-3y=-15+3y`

But `3y-3y=0`

`2x=3y-15`

Divide both sides by 2

`2/2xx x=3/2y-15/2`

But `2/2=1`

`x=3/2y-15/2` .....................(2)
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Where there is a `x` in equation (2) write `y`
Where there is a `y` in equation (2) write `x`

`color(blue)(=>y=3/2x-15/2)` .............................(3)
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`color(red)("A inverse function is a reflection about "y=x)`