Find the slope of the line that passes through (15, 29) and (57, -11).

Simplify your answer and write it as a proper fraction, improper fraction, or integer.

Verified Answer :

  • Identify the two points \((15, 29)\) and \((57, -11)\).
  • Apply the slope formula \(m = \frac{y_2 - y_1}{x_2 - x_1}\) to compute the rise over run: \(\frac{-11 - 29}{57 - 15} = \frac{-40}{42}\).
  • Simplify the resulting fraction by dividing both the numerator and the denominator by their greatest common divisor, 2.
  • The final simplified slope is \(\boxed{-\frac{20}{21}}\).

Explanation

  1. Identifying the Formula and Points

To find the slope of the line passing through two points \((x_1, y_1)\) and \((x_2, y_2)\), we use the slope formula:
\[m = \frac{y_2 - y_1}{x_2 - x_1}\]
In this problem, the given points are \((x_1, y_1) = (15, 29)\) and \((x_2, y_2) = (57, -11)\). By identifying these coordinates, we can proceed to substitute them into the slope formula to determine the slope \(m\).

  1. Calculating the Slope Expression

Substitute the identified values into the slope formula:
\[m = \frac{-11 - 29}{57 - 15}\]
First, calculate the numerator:
\[-11 - 29 = -40\]
Next, calculate the denominator:
\[57 - 15 = 42\]
Thus, the slope is given by the fraction:
\[m = \frac{-40}{42}\]

  1. Simplifying the Fraction

To simplify the fraction \(\frac{-40}{42}\), we find the greatest common divisor (GCD) of 40 and 42. Since both numbers are even, we can divide both by 2:
\[-40 \div 2 = -20\]
\[42 \div 2 = 21\]
The fraction \(\frac{-20}{21}\) cannot be simplified further, as 20 and 21 have no common factors other than 1. Therefore, the simplified slope of the line is \(-\frac{20}{21}\).

Examples

Calculating the slope is fundamental in many real-life applications. For instance, if you are designing a wheelchair ramp, the slope determines how steep or accessible the ramp will be. A slope of \(\frac{\text{rise}}{\text{run}}\) ensures that the rise of the ramp (height) relative to its run (horizontal distance) complies with safety standards, typically requiring a slope no greater than 1:12. By applying the slope formula \(\frac{y_2 - y_1}{x_2 - x_1}\), engineers and builders can precisely determine the incline of structures like roofs, roads, and staircases.