Answer:
x= -2 
Explanation:
To graph it. You know that the slope(m) is 2 and y-int is 4. 
So put a point on (0, 4), (1, 6) and (0, 2) then use your ruler and just draw a straight line hitting all these points. 
Ex. 
When x=1 
y=2x+4
y=2(1)+4
y=6
(1, 6) is a point 
To solve for x-int, make y=0 because it's on the x-axis
y=2x+4
0=2x+4
-4=2x
x=-2