Write the linear equation that gives the rule for this table.

\begin{tabular}{|c|c|}
\hline [tex]$x$[/tex] & [tex]$y$[/tex] \\
\hline 5 & 57 \\
\hline 10 & 67 \\
\hline 22 & 91 \\
\hline 23 & 93 \\
\hline
\end{tabular}

Write your answer as an equation with [tex]\(y\)[/tex] first, followed by an equals sign.

[tex]\(\square\)[/tex]



Answer :

To determine the linear equation [tex]\( y = mx + c \)[/tex] for the given table, we need to calculate the slope [tex]\( m \)[/tex] and the y-intercept [tex]\( c \)[/tex]. Let's outline the steps:

1. Identify the given points:

The table provides the following pairs of [tex]\( (x, y) \)[/tex] values:

[tex]\[ \begin{array}{ccc} x & : & 5, 10, 22, 23 \\ y & : & 57, 67, 91, 93 \\ \end{array} \][/tex]

2. Calculate the mean of [tex]\( x \)[/tex] and [tex]\( y \)[/tex]:

[tex]\[ \text{Mean of } x (\overline{x}) = 15.0 \][/tex]

[tex]\[ \text{Mean of } y (\overline{y}) = 77.0 \][/tex]

3. Find the sums needed for the slope (m):

The numerator part of the slope formula, which is the sum of the product of the differences of each [tex]\( x \)[/tex] and [tex]\( y \)[/tex] from their respective means, is calculated as follows:

[tex]\[ \text{Numerator} = \sum (x_i - \overline{x})(y_i - \overline{y}) = 476.0 \][/tex]

The denominator part, which is the sum of the squared differences of each [tex]\( x \)[/tex] from the mean of [tex]\( x \)[/tex], is:

[tex]\[ \text{Denominator} = \sum (x_i - \overline{x})^2 = 238.0 \][/tex]

4. Calculate the slope:

[tex]\[ m = \frac{\text{Numerator}}{\text{Denominator}} = \frac{476.0}{238.0} = 2.0 \][/tex]

5. Calculate the y-intercept [tex]\( c \)[/tex]:

The y-intercept can be found using the slope and the mean values calculated earlier:

[tex]\[ c = \overline{y} - m \cdot \overline{x} = 77.0 - 2.0 \cdot 15.0 = 77.0 - 30.0 = 47.0 \][/tex]

6. Form the linear equation [tex]\( y = mx + c \)[/tex]:

Using the calculated slope and intercept, the linear equation that represents the relationship between [tex]\( x \)[/tex] and [tex]\( y \)[/tex] is:

[tex]\[ y = 2.0x + 47.0 \][/tex]

Thus, the linear equation that gives the rule for the values in this table is:

[tex]\[ y = 2.0x + 47.0 \][/tex]