A line passes through the points (2,–5) and (5,–6). What is its equation in point-slope form?

1 answer

To find the equation of the line in point-slope form, we first need to determine the slope of the line that passes through the points (2, –5) and (5, –6).

The formula for the slope \( m \) between two points \((x_1, y_1)\) and \((x_2, y_2)\) is given by:

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

Using the points \((2, -5)\) and \((5, -6)\):

  • Let \((x_1, y_1) = (2, -5)\)
  • Let \((x_2, y_2) = (5, -6)\)

Now, plug these values into the slope formula:

\[ m = \frac{-6 - (-5)}{5 - 2} = \frac{-6 + 5}{5 - 2} = \frac{-1}{3} \]

Thus, the slope \( m \) is \(-\frac{1}{3}\).

Next, we can use the point-slope form of the equation of a line, which is:

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

We can choose either of the two points to use in this formula. Let's use the point (2, -5):

  • \( (x_1, y_1) = (2, -5) \)
  • \( m = -\frac{1}{3} \)

Substituting these values into the point-slope form, we get:

\[ y - (-5) = -\frac{1}{3}(x - 2) \]

This simplifies to:

\[ y + 5 = -\frac{1}{3}(x - 2) \]

So, the equation of the line in point-slope form is:

\[ y + 5 = -\frac{1}{3}(x - 2) \]