The points
$\,(x,y)\,$
that satisfy the equation
$\,x = 3\,$ (that is, $\,x + 0y = 3\,$) 
Memory Device for Vertical Lines 
The points
$\,(x,y)\,$
that satisfy the equation
$\,y = 3\,$ (that is, $\,0x + y = 3\,$) 
Memory Device for Horizontal Lines 
CONCEPT QUESTIONS EXERCISE:
On this exercise, you will not key in your answer.However, you can check to see if your answer is correct. 
PROBLEM TYPES:
