t is a horizontal line, which value is always y=4
p is a vertical line, which value is always x=-4
t: y=4
p: x=-4
n and m are linear equations:
Slope intercept form:
y=mx+b
where
m= slope
b= t-intercept
Line M.
By looking at the graph we can see that the line crosses the y-axis at y=4
So, b=4
y=mx+4
Replace x and y by a point of the line, for example (1,2), and solve for m:
2=1m+4
2-4 = m
-2=m
M: y=-2x+4
Line n
b= -1
y=mx-1
(2,1)
1=2x-1
1+1 =2x
2=2x
2/2=x
1=x
Line n : y= x-1