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To find the equation of a line, you need to have the slope of the line and a point on the line.
The slope is found using the slope formula:
Now sub in the point and slope into the equation y=mx+b to get:
`-1=-1+b` move -1 to left side
This means the equation of the line is `y=-x` .
Slope m= y2-y1/x2-x1
equatio of line: y=mx+c
this the equation.