for the line that goes up - it cuts the y-axis at - 5 (p = -5)
when we take 2 points we go from one to the other by going to the right of 1 unit and going up of 3 units (slope m : 3/1)
=> y = 3x - 5
and
for the line which goes down - it cuts the y-axis in +2 (p=2)
when we take 2 points we go from one to the other by going to the right of 2 units and going down of 1 unit (slope m : -1/2)
=> y = -1/2x + 2
=> y + 1/2x = 2
2x + 4y = 8
=> B