Question

If y varies inversely as x, and y = 18 when x = 2, find y when x = 4. (Points : 4)
9/4
9
36
144

Answer 1

y varies inversely as x so \[y = \frac{k}{x}\] substitute the first condition...y = 18 when x = 2

\[18 = \frac{k}{2}\]
\[36 = k\]

now solve the second condition...what's y when x = 4 \[y = \frac{k}{x}\] now sub in k and x \[y = \frac{36}{4}\] can you solve it now?

Answer 2

i think so.

Answer 3

great!! ^_^