Please help me understand this problem

y = 6x

Step-by-step explanation:

Choose two points on the graph of this line for the purpose of calculating the slope (rise/run).  One such point is (0, 0), which is a good choice because both x and y are exactly zero there.  Another point would be (16, 96), as the line goes through this point exactly.

Then the slope is m = rise / run = 96/16 = 6.

We'll use y = mx + b, with x = 0 and y = 0, learning immediately that b must be 0.  

Thus, the equation of this graph is y = mx + b =>  y = 6x, which is a proportional relationship.