Let a = (x1,y1) = (4,6) and b = (x2,y2) = (8,14)
Then, since the formula of the gradient (or Slope), given two points a and b is :
m = (y2 - y1) / (x2-x1) = (14 - 6) / (8 - 4) = 8 / 4 = 2
Then we know that the gradient is m = 2
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