Examples with solutions for Parts of a Triangle: Finding the ratio between dimensions in a triangle

Exercise #1

ABC is a right triangle.

BD is the median to the hypotenuse of the triangle.

Calculate the ratio between the length of BD and the length of AC.

AAABBBCCCDDD

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Recognize that triangle ABC is a right triangle with BD as the median to the hypotenuse AC.
  • Step 2: Apply the geometric property that the median to the hypotenuse of a right triangle is half the length of the hypotenuse.

Now, let's work through these steps:
Step 1: The problem states that BD is the median to the hypotenuse AC in the right triangle ABC.
Step 2: According to the geometric property of a median in a right triangle, the length of the median BD is half the hypotenuse AC AC . Therefore, BD=12AC BD = \frac{1}{2}AC .

Thus, the ratio between BD BD and AC AC can be expressed as:
BDAC=12ACAC=12 \frac{BD}{AC} = \frac{\frac{1}{2}AC}{AC} = \frac{1}{2}
This simplifies to the ratio 1:2 1:2 .

Therefore, the solution to the problem is 1:21:2.

Answer

1:2

Exercise #2

In front of you the next triangle:

Given AD median in the triangle.

Find the ratio of the length of the side BC and the length of DC.

AAABBBCCCDDD

Video Solution

Step-by-Step Solution

In triangle ABC ABC , AD AD is a median from A A to side BC BC . By definition, a median divides the opposite side into two equal segments: BD=DC BD = DC . Therefore, the total length of side BC BC is the sum of BD BD and DC DC , which simplifies to BC=BD+DC=2×DC BC = BD + DC = 2 \times DC .

We are tasked with finding the ratio BC:DC BC : DC . Given that BC=2×DC BC = 2 \times DC , we conclude the ratio is 2:1 2:1 .

Therefore, the solution to the problem is 2:1 2:1 .

Answer

2:1

Exercise #3

In front of you the next triangle:

Since AD is the median

Find the ratio of the area of the triangle ABD and the area of the triangle ADC.

AAABBBCCCDDD

Step-by-Step Solution

To solve this problem, we'll focus on the role of the median AD AD .

  • Since AD AD is a median, it divides side BC BC into two equal parts, meaning D D is the midpoint.
  • The property of a median in a triangle is that it divides the triangle into two smaller triangles of equal area.
  • Thus, ABD \triangle ABD and ADC \triangle ADC will have the same area.

Therefore, the ratio of the area of ABD \triangle ABD to the area of ADC \triangle ADC is 1:1 1:1 .

Answer

1:1