Parts of a Triangle Practice Problems & Worksheets

Master triangle terminology with interactive practice on heights, medians, angle bisectors, and perpendicular bisectors. Build geometry skills step-by-step.

📚What You'll Master in Triangle Parts Practice
  • Identify and draw triangle heights from vertices to opposite sides
  • Locate medians that divide triangle sides into equal segments
  • Construct angle bisectors that create equal angles at vertices
  • Draw perpendicular bisectors from midpoints of triangle sides
  • Find midsegments connecting midpoints of two triangle sides
  • Distinguish between different types of triangle lines and their properties

Understanding Parts of a Triangle

Complete explanation with examples

Terms used in triangle calculations

  • Line

A line is a general term for straight lines (hence its name) that extend from a specific point on the triangle.

  • Height

Height is a line that extends from a specific vertex and reaches perpendicularly to the opposite side, creating a right angle. The height is marked with the letter h (from the word height).

  • Median

The median is also a line extending from a specific vertex to the opposite side, but it reaches exactly the middle of the opposite side and divides it into two equal parts.

  • Angle Bisector

An angle bisector is a line that extends from a specific vertex and actually divides the vertex into two equal angles.

  • Perpendicular Bisector

A perpendicular bisector is a line that extends from the middle of a side perpendicular to it.

  • Midsegment

A midsegment is a line that connects the midpoints of two sides and is parallel to the third side, with its length being half of it.

  • Opposite Side

An opposite side is the side that is located opposite to a specific vertex and does not pass through it.

Diagram of a triangle ABC illustrating key geometric concepts: height (H) in green, median in blue, angle bisector in red, perpendicular bisector from CB in orange, midsegment in purple, and the side opposite to vertex A highlighted in orange. Labels are color-coded for clarity.

Detailed explanation

Practice Parts of a Triangle

Test your knowledge with 36 quizzes

Given the following triangle:

Write down the height of the triangle ABC.

AAABBBCCCDDD

Examples with solutions for Parts of a Triangle

Step-by-step solutions included
Exercise #1

True or false:

DE not a side in any of the triangles.
AAABBBCCCDDDEEE

Step-by-Step Solution

To solve the problem of determining whether DE is not a side in any of the triangles, we will methodically identify the triangles present in the diagram and examine their sides:

  • Identify triangles in the diagram. The diagram presented forms a right-angled triangle ABC with additional lines forming smaller triangles within.
  • Triangles formed: Triangle ABC (major triangle), Triangle ABD, Triangle BEC, and Triangle DBE.
  • Let's examine the sides of these triangles:
    • Triangle ABC has sides AB, BC, and CA.
    • Triangle ABD has sides AB, BD, and DA.
    • Triangle BEC has sides BE, EC, and CB.
    • Triangle DBE has sides DB, BE, and ED.
  • Notice that while point D is used, the segment DE is only part of line BE and isn't listed as a direct side of any triangle.

Therefore, the claim that DE is not a side in any of the triangles is indeed correct.

Hence, the answer is True.

Answer:

True

Video Solution
Exercise #2

Is DE side in one of the triangles?
AAABBBCCCDDDEEE

Step-by-Step Solution

Since line segment DE does not correspond to a full side of any of the triangles present within the given geometry, we conclude that the statement “DE is a side in one of the triangles” is Not true.

Answer:

Not true

Video Solution
Exercise #3

True or false:

AB is a side of the triangle ABC.

AAABBBCCC

Step-by-Step Solution

To solve this problem, let's clarify the role of AB in the context of triangle ABC by analyzing its diagram:

  • Step 1: Identify the vertices of the triangle. According to the diagram, the vertices of the triangle are points labeled A, B, and C.
  • Step 2: Determine the sides of the triangle. In any triangle, the sides are the segments connecting pairs of distinct vertices.
  • Step 3: Identify AB as a line segment connecting vertex A and vertex B, labeled directly in the diagram.

Considering these steps, line segment AB connects vertex A with vertex B, and hence, forms one of the sides of the triangle ABC. Therefore, AB is indeed a side of triangle ABC as shown in the diagram.

The conclusion here is solidly supported by our observation of the given triangle. Thus, the statement that AB is a side of the triangle ABC is True.

Answer:

True

Video Solution
Exercise #4

True or false:

AD is a side of triangle ABC.

AAABBBCCC

Step-by-Step Solution

To determine if line segment AD is a side of triangle ABC, we need to agree on the definition of a triangle's side. A triangle consists of three sides, each connecting pairs of its vertices. In triangle ABC, these sides are AB, BC, and CA. Each side is composed of a direct line segment connecting the listed vertices.

In the diagram provided, there is no indication of a point D connected to point A or any other vertex of triangle ABC. To claim AD as a side, D would need to be one of the vertices B or C, or a commonly recognized point forming part of the triangle’s defined structure. The provided figure and description do not support that AD exists within the given triangle framework, as no point D is defined within or connecting any existing vertices.

Therefore, according to the problem's context and based on the definition of the sides of a triangle, AD cannot be considered a side of triangle ABC. It follows that the statement "AD is a side of triangle ABC" should be deemed not true.

Answer:

Not true

Video Solution
Exercise #5

True or false:

BC is a side of triangle ABC.

AAABBBCCC

Step-by-Step Solution

To solve this problem, we must determine whether BC is indeed a side of triangle ABC. A triangle consists of three vertices connected by three line segments that form its sides.

Firstly, observe the triangle labeled in the diagram with vertices A, B, and C. For triangle ABC, the sides are composed of the segments that connect these points.

  • The three line segments connecting the vertices are:
    • AB AB , connecting points A and B;
    • BC BC , connecting points B and C; and
    • CA CA , connecting points C and A.

Among these, BC is clearly listed as one of the segments connecting two vertices of the triangle. Therefore, BC is indeed a side of triangle ABC.

Hence, the statement is True.

Answer:

True

Video Solution

Frequently Asked Questions

What is the difference between a height and a median in a triangle?

+
A height (altitude) is a line from a vertex perpendicular to the opposite side, forming a 90° angle. A median is a line from a vertex to the midpoint of the opposite side, dividing that side into two equal parts. The height focuses on perpendicularity, while the median focuses on bisecting the opposite side.

How do you identify the opposite side of a triangle vertex?

+
The opposite side is the side that doesn't touch the vertex you're looking at. For example, in triangle ABC, the opposite side to vertex A is side BC. The opposite side is always across from the vertex, never connected to it.

What makes an angle bisector different from other triangle lines?

+
An angle bisector divides an angle at a vertex into two equal smaller angles. Unlike heights or medians that go to the opposite side, angle bisectors focus on splitting the angle itself. If angle A is 60°, its angle bisector creates two 30° angles.

How long is a midsegment compared to the third side of a triangle?

+
A midsegment is always exactly half the length of the third side (the side it's parallel to). This is the Triangle Midsegment Theorem. For example, if the third side is 10 units long, the midsegment will be 5 units long.

Where does a perpendicular bisector start in a triangle?

+
A perpendicular bisector starts from the midpoint of any triangle side and extends perpendicular (at 90°) to that side. It doesn't originate from a vertex like heights, medians, or angle bisectors do. Instead, it bisects the side itself.

Can a triangle have multiple heights, medians, and angle bisectors?

+
Yes! Every triangle has exactly three of each: three heights (one from each vertex), three medians (one from each vertex), and three angle bisectors (one for each angle). Each serves a different geometric purpose in triangle analysis.

What tools do I need to draw triangle parts accurately?

+
You'll need: 1) A ruler for measuring and drawing straight lines, 2) A protractor for measuring angles and creating perpendicular lines, 3) A compass for finding midpoints and creating equal segments. These tools help ensure your triangle constructions are precise.

Why are triangle parts important in geometry problems?

+
Triangle parts help solve area calculations, prove congruence, find missing measurements, and understand triangle properties. Heights are used in area formulas, medians help locate centroids, and angle bisectors are crucial for angle relationships and triangle similarity problems.

More Parts of a Triangle Questions

Continue Your Math Journey

Practice by Question Type