Triangle ABC

is drawn on a coordinate plane with vertices A(−3,−3)
, B(0,6)
, and C(4,−3)
and medians indicating the midpoint of each of the lines AB
, BC
, and CA
. Prove the medians meet at a single point by finding the centroid.(1 point)
Responses which answer is correct and why

(0,13)
left parenthesis 0 comma Start Fraction 1 over 3 End Fraction right parenthesis

(16,3)
left parenthesis Start Fraction 1 over 6 End Fraction comma 3 right parenthesis

(13,0)
left parenthesis Start Fraction 1 over 3 End Fraction comma 0 right parenthesis

(13,1)
left parenthesis Start Fraction 1 over 3 End Fraction comma 1 right parenthesis
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1 answer

To find the centroid (the point where the medians of the triangle meet), we can use the formula for the centroid given by the coordinates of the triangle's vertices \( A(x_1, y_1) \), \( B(x_2, y_2) \), and \( C(x_3, y_3) \):

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

Substituting the coordinates of points A, B, and C:

  • \( A(-3, -3) \)
  • \( B(0, 6) \)
  • \( C(4, -3) \)

Calculating the x-coordinate of the centroid:

\[ x_G = \frac{-3 + 0 + 4}{3} = \frac{1}{3} \]

Next, calculating the y-coordinate of the centroid:

\[ y_G = \frac{-3 + 6 - 3}{3} = \frac{0}{3} = 0 \]

Thus, the centroid \( G \) is at:

\[ G\left(\frac{1}{3}, 0\right) \]

Now we compare this with the provided options:

  1. (0, 13)
  2. \( \left(0, \frac{1}{3}\right) \)
  3. \( \left(\frac{1}{3}, 0\right) \)
  4. \( \left(\frac{1}{3}, 1\right) \)

The correct answer is:

\( \left(\frac{1}{3}, 0\right) \)

Reason why this is correct:

This result shows that the medians of triangle ABC indeed meet at the centroid, as the calculations align with the theoretical definition of a centroid for a triangle. The coordinates match exactly with option 3.