Question

How do you write an equation of a line with point (-1,4) and slope -1?

Answer 1

`y = -x + 3`

Explanation:

The general equation of the straight line is :
`" "`
`y - y_0 = a(x - x_0)`
`" "`
`a " "`is the slope.
`" "`
`(x_0,y_0)" "`is the point the straight line passes through.
`" "`
Here `a =-1" " x_0=-1" "and y_0 = 4`
`" "`
`y - 4 = -1(x - (-1))`
`" "`
`rArr y - 4 = -1(x + 1)`
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`rArr y - 4 = -x - 1`
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`rArr y = -x -1 +4`
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`rArr y = -x + 3`
`" "`
`" "`
Hence ,`" "y = -x + 3`