The equation of a line in the slope intercept form is expressed as
y = mx + b
where
m represents slope
b represents y intercept
The formula for finding slope is
m = (y2 - y1)/(x2 - x1)
From the graph,
When x1 = 1, y1 = - 2
when x2 = 2, y = 1
Slope = (1 - - 2)/(2 - 1) = 3/1
Slope = 3
The y intercept is the value of y at the point where the line cuts through the y axis. Thus, y intercept = - 5
To write the equation of the line, we would substitute m = 3 and b = - 5 into the slope intercept equation. Thus, the equation of the line is
y = 3x - 5