Math Problem Statement

The vertices of a triangle are the points A (-3,4); B (5,-2) & C (4,7). If D is the midpoint of side AB, calculate the lenght of the median DC.

Solution

To calculate the length of the median DCDC, we can follow these steps:

Step 1: Find the midpoint DD of side ABAB.

The coordinates of the midpoint D(x1,y1)D(x_1, y_1) of a line segment joining points A(xA,yA)A(x_A, y_A) and B(xB,yB)B(x_B, y_B) are given by:

D=(xA+xB2,yA+yB2)D = \left(\frac{x_A + x_B}{2}, \frac{y_A + y_B}{2}\right)

Substituting the coordinates of A(3,4)A(-3, 4) and B(5,2)B(5, -2):

D=(3+52,4+(2)2)=(22,22)=(1,1)D = \left(\frac{-3 + 5}{2}, \frac{4 + (-2)}{2}\right) = \left(\frac{2}{2}, \frac{2}{2}\right) = (1, 1)

So, the coordinates of point DD are (1,1)(1, 1).

Step 2: Calculate the length of the median DCDC.

The length of a line segment DCDC connecting points D(x1,y1)D(x_1, y_1) and C(xC,yC)C(x_C, y_C) is given by:

DC=(xCx1)2+(yCy1)2DC = \sqrt{(x_C - x_1)^2 + (y_C - y_1)^2}

Substituting the coordinates D(1,1)D(1, 1) and C(4,7)C(4, 7):

DC=(41)2+(71)2=32+62=9+36=45=35DC = \sqrt{(4 - 1)^2 + (7 - 1)^2} = \sqrt{3^2 + 6^2} = \sqrt{9 + 36} = \sqrt{45} = 3\sqrt{5}

Final Answer:

The length of the median DCDC is 353\sqrt{5}.

Do you want details on any step or have further questions?


Related Questions:

  1. How would you calculate the length of the other medians in this triangle?
  2. Can you find the centroid of the triangle ABCABC?
  3. What is the perimeter of triangle ABCABC?
  4. How would you determine if triangle ABCABC is right-angled?
  5. What is the area of triangle ABCABC using the coordinates of the vertices?

Tip: The centroid of a triangle divides each median into two segments, where the longer segment is twice the length of the shorter one.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Coordinate Geometry
Midpoint Formula
Distance Formula

Formulas

Midpoint formula
Distance formula

Theorems

-

Suitable Grade Level

Grades 9-12