Direct variation

Lessons

1. Identifying direct variations by table of values
   Do the following tables of values represent direct variation?
   
   
   
   
   
2. Identifying direct variations
   Which of the following represent direct variation?
   
   A. $y$ = 2
   
   B. $y$ = 3.1$x$
   
   C. $y = - \frac{7x}{9}$
   
   D. $xy$ = 191
   
   E. $y$ = 8$x$ + 5
   
3. Variable $y$ varies directly with $x$. Determine $m$ and $n$
   
   
4. If $a$ varies directly as $b$, and $b$ = 4 when $a$ = 16, find $a$ when $b = \frac{3}{2}$
5. If the volume of an object varies directly as the cube of its height, and the volume equals 40$ft^{3}$ when the height is 2$ft$, find the object's volume when its height equals $\frac{1}{3} ft$