Write an equation to describe the variation. Use k for the constant of proportionality.
a varies inversely as t

The equation of variation is a t = k or  a =

Step-by-step explanation:

Inverse variation is a relationship between two variables which can be modeled by an equation where the product of two variables is equal to a constant, and this  constant is called constant of proportionality

Ex: if y varies inversely with x ⇒ y ∝

The equation is y = OR  yx = k, where k is the constant of proportionality

∵ a varies inversely as t

∴ a ∝

- Put them in the equation by using k the constant of proportionality

∴ a =

- Multiply both sides by t

∴ a t = k

The equation of variation is a t = k  or  a =

47 - 90 = 43

43 - 180 = x

x = 137