Triangle ABC is drawn on a coordinate plane with vertices A (-2, - 3)

, B (1, 0), and C (-2, 2) and medians indicating the midpoint of each of the line segments AB, BC', and C'A . Prove that the medians meet at a single point by finding the centroid. (1 point)
O (0, 0)
•(0,号)
0 (0,-)
〇(-1,)

1 answer

To find the centroid of triangle \( ABC \), we can use the formula for the centroid \( G \) of a triangle with vertices \( A(x_1, y_1) \), \( B(x_2, y_2) \), and \( C(x_3, y_3) \):

\[ G\left( \frac{x_1 + x_2 + x_3}{3}, \frac{y_1 + y_2 + y_3}{3} \right) \]

Given the vertices of the triangle:

  • \( A(-2, -3) \)
  • \( B(1, 0) \)
  • \( C(-2, 2) \)

We can substitute these coordinates into the centroid formula.

Calculating the x-coordinate of the centroid:

\[ x_G = \frac{-2 + 1 - 2}{3} = \frac{-3}{3} = -1 \]

Calculating the y-coordinate of the centroid:

\[ y_G = \frac{-3 + 0 + 2}{3} = \frac{-1}{3} \]

Thus, the coordinates of the centroid \( G \) are:

\[ G\left(-1, -\frac{1}{3}\right) \]

This calculation confirms that the medians of triangle \( ABC \) do indeed meet at a single point, which is the centroid \( G \).

In summary, the centroid of triangle \( ABC \) is:

\[ G\left(-1, -\frac{1}{3}\right) \]