Write and graph the inverse variation in which y = 8 when x = –4.

For this case we have that an inverse variation in a function is given by:
 
 For this case, we must find the value of the constant k.
 To do this, we substitute the values of x = -4, y = 8.
 We have then:
 
 Clearing k we have:
 
 Substituting the value of k we have that the inverse variation is:
 
 Note: see attached image.
 
 
 See attached image.