Answer:
y = m x + b equation of a straight line
m = (y2 - y1) / (x2 - x1) slope of line
m = (17 - 10) / (-36 - 48) = 7 / -84 = -1 / 12
y = -x / 12 + b equation of line
Or b = y + x / 12
If y = 10 and x = 48 then b = 10 + 48 / 4 = 14
if y = 17 and x = -36 then b = 17 - 36 / 12 = 14
So b = 14 and y = -x / 12 + 14