The first step is to find the slope
m = (y2-y1)/(x2-x1)
m = (22-18)/(9-5)
=4/4
=1
The slope intercept form of a line is
y = mx+b where m is the slope and b is the y intercept
y = 1x+b
Using a point (5,18) on the line
18 = 1(5)+b
18-5 = b
13 = y
y = 1x +13
y = x+13
