How do you find the direct variation equation if z is directly proportional to r when $r = 412$ $r=412$ , $z = 51.5$ $z=51.5$ ?

Question

3006 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2014-10-26T02:09:13

Direct variations are expressed in the form

$y = k x$ $y = kx$

where $k$ $k$ is a constant

For your problem, $z$ $z$ is directly proportional to $r$ $r$

$z = k r$ $z = kr$

$51.5 = k (412)$ $51.5 = k(412)$

$k = \frac{51.5}{412}$ $k = 51.5/412$

$k = \frac{1}{8}$ $k = 1/8$

$\Rightarrow z = \frac{1}{8} r$ $=> z = 1/8r$

How do you find the direct variation equation if z is directly proportional to r when r=412r=412, z=51.5z=51.5?