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If y varies directly with x, and if y = 12 when x = 3, how do you find the direct variation equation?

1 Answer

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Final Answer:

If
\(y\) varies directly with
\(x\) and
\(y = 12\) when
\(x = 3\) , you can find the direct variation equation by using the formula
\(y = kx\) , where
\(k\) is the constant of variation.

Step-by-step explanation:

In the case of direct variation, the relationship between
\(y\) and
\(x\) is expressed as
\(y = kx\), where
\(k\) is a constant. To find the constant of variation
(\(k\)), substitute the given values for \(y\) and \(x\) into the equation.

Given that
\(y = 12\) when
\(x = 3\):


\[12 = k * 3\]

Solving for
\(k\):


\[k = (12)/(3) = 4\]

Now that you know
\(k = 4\), you can write the direct variation equation:


\[y = 4x\]

So, in this case, the direct variation equation is
\(y = 4x\).

In summary, to find the direct variation equation, substitute the given values into the
\(y = kx\) formula and solve for the constant of variation
(\(k\)).

User Jshen
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