1. Example: find the equation of the line on this graph...
From this graph, we can determine two points: the x- intercept (3,0) and the y-intercept (0,6)
Since the y-intercept is 6, we already know our ‘c’ value in the equation which is 6 (so far, we have y=mx+6 as our equation and we need to just find ‘m’)
We now need to find the ‘m’ value or the gradient using: (x1, y1) and (x2, y2) where:
x1 is 3, x2 is 0
y1 is 0, y2 is 6
So, we use the formula:
m = (6-0)/(0-3)
m = 6/-3
m = -2
Now we know our m and c values, we can plug those into the equation y=mx+c to determine the equation of the line:
y = -2x + 6