The equation of a line in the slppe intercept form is expressed as
y = mx + c
where
m = slope
c = y intercept
The formula for determining the slope is expressed as
m = (y2 - y1)/(x2 - x1)
where
y2 and y1 are the values on the y axis corresponding to the final and initial points on the line
x2 and x1 are the values on the x axis corresponding to the final and initial points on the line
Looking at the points on the line,
x1 = - 2, y1 = - 4
x2 = 4, y2 = 8
m = (8 - - 4)/(4 - - 2) = (8 + 4)/(4 + 2) = 12/6
m = 2
The y intercept, c is the point where the line cuts across the y axis. Looking at the graph, c = 0
By substituting m = 2 and c = 0 into the slope intercept equation, the equation of the line is
y = 2x
