# F varies inversely as the square of d and f=50 when d=10, how do you express f in terms of d?

Jul 4, 2016

$F = \frac{5000}{d} ^ 2$

#### Explanation:

Write it as an inverse variation first.

$F \propto \frac{1}{d} ^ 2 \text{ multiply by k}$

$F = \frac{k}{d} ^ 2 \text{ find the value of k}$

$k = F \times {d}^{2} \Rightarrow 50 \times {10}^{2} = 5000$

$F = \frac{5000}{d} ^ 2$