The variable [tex]$y$[/tex] varies directly with the variable [tex]$x$[/tex].

[tex]\[
\begin{tabular}{|c|c|}
\hline
$x$ & $y$ \\
\hline
2 & 3 \\
\hline
10 & 15 \\
\hline
14 & \\
\hline
\end{tabular}
\][/tex]

If the value of [tex]$x$[/tex] is 14, what is the value of [tex]$y$[/tex]?

[tex]$\square$[/tex]



Answer :

When dealing with direct variation between two variables, [tex]\( y \)[/tex] varies directly with [tex]\( x \)[/tex], which can be expressed mathematically as [tex]\( y = kx \)[/tex], where [tex]\( k \)[/tex] is the constant of proportionality.

Given the values of [tex]\( x \)[/tex] and [tex]\( y \)[/tex]:

1. [tex]\( x_1 = 2 \)[/tex] and [tex]\( y_1 = 3 \)[/tex]
2. [tex]\( x_2 = 10 \)[/tex] and [tex]\( y_2 = 15 \)[/tex]

First, we need to determine the constant of proportionality [tex]\( k \)[/tex]. We can use any of the pairs [tex]\((x, y)\)[/tex] to find [tex]\( k \)[/tex]. Let's use the first pair to find [tex]\( k \)[/tex]:

[tex]\[ y_1 = kx_1 \][/tex]
[tex]\[ 3 = k \cdot 2 \][/tex]

Solving for [tex]\( k \)[/tex]:

[tex]\[ k = \frac{3}{2} = 1.5 \][/tex]

Now, we have established that [tex]\( k = 1.5 \)[/tex].

Next, we use this constant of proportionality to find the value of [tex]\( y \)[/tex] when [tex]\( x = 14 \)[/tex]:

[tex]\[ y = kx \][/tex]
[tex]\[ y = 1.5 \cdot 14 \][/tex]

Calculating the value:

[tex]\[ y = 21 \][/tex]

So, the value of [tex]\( y \)[/tex] when [tex]\( x = 14 \)[/tex] is [tex]\( 21 \)[/tex].