Inverse Variation

 1) In an inverse variation, the values

of the two x and y change in an opposite manner - as one value increases, the other decreases.

• The more games you play (x), the less errors you make (Y).

• X variable increases while y value decreases.• An inverse variation between 2 variables, y

and x, is a relationship that is expressed as:• Y= k

x

x (games played) 1 2 3 4

y (errors per game) 25 20 15 10

2)

Graph for direct variation is linear, while the graph of inverse variation is not linear. Rather, it is a hyperbola:

Direct variation & Inverse variation

To find K (constant)

Y= k

X

Equation

Y= K · X

To find K (constant)

K = XY

Equation

Y= K

X

examplesa) Y = 3

6 x (multiply both sides by 6 to isolate variable)

Equation would be: y= 18

x

b) x= 5 y= 9 K= x · y K = 45

Equation: y= 45

x