Gradient is the difference between the y-axis and the x-axis
Gradient = y2-y1/x2-x1
Choose any two point making a triangle
Line B (0,8) (4,0)
This makes a triangle please go look at the graph once again! The the triangle should not have half squares but full!
Line A (5,14)(2,2)
Now plug in the variable
The difference between the Y and X
Line B 0-8/4-0
Line B gradient =-2
Line A 2-14/2-5
Line A gradient = +4
Finalized answer
Line B gradient = -2
Line A gradient = +4