Assume y varies inversely as $x, if y = 7 when x = 6$ $x," if " y=7 " when " x=6$ , how do you find y when $x = - 12$ $x=-12$ ?

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Answer 1 · 2017-07-29T14:42:52

$y = - 3.5$ $y = -3.5$

Write the information as in inverse proportion first.

$y \propto \frac{1}{x}$ $y prop 1/x$

Make an equation by multiplying by the constant $k$ $k$

$y = \frac{k}{x} \Rightarrow k = x y$ $y = k/x" "rArr k = xy$

Find the value for $k$ $k$ from the information given.

$k = 6 \times 7 = 42$ $k = 6 xx7 = 42$

$:. y= 42/x$

Now find the required value of $y$ :

$y = 42/-12$

$y = -3.5$

Assume y varies inversely as x," if " y=7 " when " x=6x, if y=7 when x=6x," if " y=7 " when " x=6, how do you find y when x=-12x=−12x=-12?