+266 Determine whether y varies directly with x, if so, find the constant of variation of k and write the equation.
| x | y |
7 | 11 |
| 8 | 13 |
| 9 | 15 |
| 10 | 17 |
Can you show steps too! 
+129899 Notice that, when y changes by 2, x changes by 1.......so the "constant of variation" is just the slope which is : change in y / change in x = 2/1 = 2
So.....using the point (7, 11) and the slope....we can write the general equation using the slope-intercept form as :
y =(2)(x - 7) + 11 simplify
y = 2x - 14 + 11
y = 2x - 3
