The graph of a linear function passes through the points (6,

–7) and (9, –13/2). Write an equation for the function in the form y = mx + b.
y =

1 answer

To find the equation of the linear function that passes through the points (6, –7) and (9, –13/2), we first need to calculate the slope \( m \) of the line using the formula:

\[ m = \frac{y_2 - y_1}{x_2 - x_1} \]

Here, \((x_1, y_1) = (6, -7)\) and \((x_2, y_2) = (9, -\frac{13}{2})\).

Substituting these coordinates into the formula:

\[ m = \frac{-\frac{13}{2} - (-7)}{9 - 6} \]

We can simplify this step by step. First, convert -7 to a fraction:

\[ -7 = -\frac{14}{2} \]

Now substituting back:

\[ m = \frac{-\frac{13}{2} + \frac{14}{2}}{3} = \frac{\frac{1}{2}}{3} = \frac{1}{6} \]

Thus, the slope \( m \) is \( \frac{1}{6} \).

Next, we use the point-slope form of the equation:

\[ y - y_1 = m(x - x_1) \]

Using the point (6, -7):

\[ y - (-7) = \frac{1}{6}(x - 6) \]

This simplifies to:

\[ y + 7 = \frac{1}{6}x - 1 \]

Now, subtract 7 from both sides:

\[ y = \frac{1}{6}x - 1 - 7 \]

This gives:

\[ y = \frac{1}{6}x - 8 \]

Thus, the equation of the linear function in the form \( y = mx + b \) is:

\[ \boxed{y = \frac{1}{6}x - 8} \]