Question

If y varies directly as x and y is 180 when x is n and y is n when x is 5, what is the value of n?

Answer 1

A direct variation has an equation of this form:
\[y=kx\]

Answer 2

Plug in x and y and find k

Answer 3

The two equations used in this case are 180=kn and n=5k. Plug 5k into 180=kn to get \[180=5k^{2}\]. Now solve this to get k=6. 180=6n so n=30.

Answer 4

How did you get k to equal 6?