# If x varies inversely with y and x = 6 when y = 10, how do you find y when x = 8?

Apr 2, 2018

Set up an equation $x = \frac{1}{y}$ substitute to find the constant
$x \times y = C$ Then substitute again to find the new y

#### Explanation:

 x =C?y

$6 = \frac{C}{10}$ multiply both sides by 10

$6 \times 10 = \frac{C}{10} \times 10$ This gives

$60 = C .$ Now substitute x for 8 in the equation and 60 for C

$8 = \frac{60}{y}$ multiply both sides by y

$8 \times y = \frac{60}{y} \times y$ This gives

$8 y = 60$ now divide both sides by 8

$8 \frac{y}{8} = \frac{60}{8}$ The answer is

$y = 7.5$

As x gets bigger y gets smaller in an inverse relationship.