Use coordinate geometry to determine the most precise type of quadrilateral given A(-6,4), B(-3, 5), C(0, 2), and D(-3, 1). All work needs to be shown to support your answer.

1 answer

To determine the type of quadrilateral formed by the points A(-6, 4), B(-3, 5), C(0, 2), and D(-3, 1), we can find the lengths of the sides and the slopes of the segments formed by these points. Additionally, we can check the angles to understand the properties of the quadrilateral.

  1. Calculate the lengths of the sides (using the distance formula): The distance formula is given by: \[ d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} \]

    • \(AB\): \[ AB = \sqrt{((-3) - (-6))^2 + (5 - 4)^2} = \sqrt{(3)^2 + (1)^2} = \sqrt{9 + 1} = \sqrt{10} \]

    • \(BC\): \[ BC = \sqrt{(0 - (-3))^2 + (2 - 5)^2} = \sqrt{(3)^2 + (-3)^2} = \sqrt{9 + 9} = \sqrt{18} = 3\sqrt{2} \]

    • \(CD\): \[ CD = \sqrt{((-3) - 0)^2 + (1 - 2)^2} = \sqrt{(-3)^2 + (-1)^2} = \sqrt{9 + 1} = \sqrt{10} \]

    • \(DA\): \[ DA = \sqrt{((-6) - (-3))^2 + (4 - 1)^2} = \sqrt{(-3)^2 + (3)^2} = \sqrt{9 + 9} = \sqrt{18} = 3\sqrt{2} \]

  2. Summarize the side lengths:

    • \(AB = \sqrt{10}\)
    • \(BC = 3\sqrt{2}\)
    • \(CD = \sqrt{10}\)
    • \(DA = 3\sqrt{2}\)

    This shows that \(AB = CD\) and \(BC = DA\), indicating that opposite sides are equal.

  3. Calculate the slopes of the sides to analyze angles: The slope formula is given by: \[ m = \frac{y_2 - y_1}{x_2 - x_1} \]

    • Slope of \(AB\): \[ m_{AB} = \frac{5 - 4}{-3 - (-6)} = \frac{1}{3} \]

    • Slope of \(BC\): \[ m_{BC} = \frac{2 - 5}{0 - (-3)} = \frac{-3}{3} = -1 \]

    • Slope of \(CD\): \[ m_{CD} = \frac{1 - 2}{-3 - 0} = \frac{-1}{-3} = \frac{1}{3} \]

    • Slope of \(DA\): \[ m_{DA} = \frac{4 - 1}{-6 - (-3)} = \frac{3}{-3} = -1 \]

  4. Analysis of the slopes:

    • The slopes of \(AB\) and \(CD\) are equal (\(\frac{1}{3}\)), indicating that these sides are parallel.
    • The slopes of \(BC\) and \(DA\) are equal (-1), indicating that these sides are also parallel.

Since both pairs of opposite sides are equal and parallel, this confirms that the quadrilateral is a parallelogram.

  1. Conclusion: Since the quadrilateral has opposite sides that are equal and parallel, we classify the quadrilateral as a parallelogram.

Thus, the quadrilateral formed by the points A(-6, 4), B(-3, 5), C(0, 2), and D(-3, 1) is a parallelogram.