The required equation of a line is y = -3x- 1
The equation of a line in slope-intercept form is expressed as:
y = mx + b
where
m is the slope
b is the y-intercept
Using the coordinate point (0, -1) and (-1, 2)
Slope = 2-(-1)/-1-0
Slope = 3/-1
Slope =-3
Since the line crosses the y-axis at (0, -1), hence the value of b is -1
Determine the equation
y = mx + b
y = -3x + (-1)
y = -3x- 1
Hence the required equation of a line is y = -3x- 1
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