we have that
2x + y = 4
to graph this equation we will look for the x and y intercepts
step 1
find the x intercepts
y=0
2x+0=4-----> x=4/2-----> x=2
the point is (2,0)
step 2
find the y intercepts
x=0
0+y=4-----> y=4
the point is (0,4)
step 3
with the two points graph the line
see the attached figure
