Question

how can you show that two objects are proportional with a graph?

Answer 1

So this is our table:

               -----------------
x-values | a b c d e f  |
               -----------------
y-values | g h  i  j k l   |
               -----------------

You can know that the values in the table are proportional if:

$\frac{a}{g}=\frac{b}{h} =\frac{c}{i}=\frac{d}{j}=\frac{e}{k}=\frac{f}{l}$

Hope that helps :)