step 1
Find out the equation of the line
y=mx+b
we have
m=1/4
b=-6
substitute
y=(1/4)x-6
step 2
Find out the intercepts
y-intercept (value of y when the value of x=0)
For x=0
y=(1/4)(0)-6
y=-6
y-intercept is (0,-6)
x-intercept (value of x when the value of y=0)
For y=o
0=(1/4)x-6
x=24
x-intercept is (24,0)
step 3
Graph the line
Plot the intercepts and join them to graph the line
see the attached figure