# Assume that y varies directly as x. If y = 4 when x = 0.5, how do you find y when x = 2?

Apr 16, 2016

At $x = 2 \text{ ; } y = 16$

#### Explanation:

Let $k$ be the constant of variation then we have:

$y = k x$

Given condition y=4 ; x=1/2

$\implies 4 = k \times \frac{1}{2}$

Multiply both sides by 2

$\implies 8 = k \times 1$

$k = 8$

So we have

$y = 8 x$
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Suppose $x = 2$ then we have

$y = 8 \times 2 = 16$