Triangle Median Problem: Find the Ratio of BC to DC

Median Properties with Ratio Calculation

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

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step video solution

Watch the teacher solve the problem with clear explanations
00:00 Determine the ratio between BC and DC
00:03 The entire side equals the sum of its parts
00:18 The segments are equal according to the given data
00:26 Substitute in DC for BD
00:37 Determine the ratio between BC and DC
00:47 Simplify wherever possible
00:51 This is the solution

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

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

2

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 .

3

Final Answer

2:1

Key Points to Remember

Essential concepts to master this topic
  • Definition: A median divides the opposite side into two equal segments
  • Technique: Since BD=DC BD = DC , then BC=2×DC BC = 2 \times DC
  • Check: Verify ratio by confirming BC:DC=2DC:DC=2:1 BC:DC = 2DC:DC = 2:1

Common Mistakes

Avoid these frequent errors
  • Confusing which segments are equal in a median
    Don't think BD:DC equals 1:1 means BC:DC also equals 1:1 = wrong ratio! This ignores that BC contains both BD and DC segments. Always remember BC = BD + DC, so if BD = DC, then BC = 2 × DC.

Practice Quiz

Test your knowledge with interactive questions

Is the straight line in the figure the height of the triangle?

FAQ

Everything you need to know about this question

What exactly does a median do in a triangle?

+

A median is a line segment from any vertex to the midpoint of the opposite side. It always divides that side into two equal parts, no matter what type of triangle you have!

Why isn't the ratio BC:DC equal to 1:1?

+

Because BC is the whole side while DC is only half of it! Since the median creates BD=DC BD = DC , we have BC=BD+DC=DC+DC=2DC BC = BD + DC = DC + DC = 2DC .

Does this ratio work for any triangle with a median?

+

Absolutely! This 2:1 ratio between the whole side and half the side is true for every triangle, regardless of its shape or size. It's a fundamental property of medians.

How can I remember this concept?

+

Think of it like a pizza slice! If you cut a slice exactly in half, the whole slice is twice as big as each half slice. Same idea: whole side = 2 × half side.

What if the problem asked for DC:BC instead?

+

Just flip the ratio! If BC:DC=2:1 BC:DC = 2:1 , then DC:BC=1:2 DC:BC = 1:2 . Always pay attention to which measurement comes first in the question.

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Triangle questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime

More Questions

Click on any question to see the complete solution with step-by-step explanations