Answer:
y= 3/4x
Step-by-step explanation:
Points on the graph
the equation based on the difference in points:
 
        
                    
             
        
        
        
2+3t
When t is 1
2+3(1)
2+3
5
When t is 4
2+3(4)
2+12
14
        
                    
             
        
        
        
The 4th option. 
The values with no x or y attached are the y intercept
6x - 7y = 21
Subtract 6x from both sides 
6x - 7y - 6x = 21 - 6x
-7y = 21 - 6x
Divide both sides by - 7
-7y/-7 = 21/-7 - 6x/-7
Y = -3 +6x/7
The why intercept, -3 is the same as the one in the question