Simple....

x<6
This means that on your graph at 6 it's a circle (not colored in) and it goes to the left indefinitely...
Thus, your answer.
The value of x is 5. Angle one and four are vertical. You can do this by writing 7x = 3x + 20. Isolate the variable by moving 3x to the other side. If you do this, 3x becomes negative, and you end up with 7x-3x = 20 --> 4x = 20.
x=5.