Examples with solutions for Types of Triangles: Identifying and defining elements

Exercise #1

Is the triangle in the drawing a right triangle?

Step-by-Step Solution

Due to the presence of the 90 degree angle symbol we can determine that this is indeed a right-angled triangle.

Answer

Yes

Exercise #2

In a right triangle, the two sides that form a right angle are called...?

Step-by-Step Solution

In a right triangle, there are specific terms for the sides. The two sides that form the right angle are referred to as the legs of the triangle. To differentiate, the side opposite the right angle is called the hypotenuse, which is distinct due to being the longest side. Hence, in response to the problem, the sides forming the right angle are correctly identified as Legs.

Answer

Legs

Exercise #3

In a right triangle, the side opposite the right angle is called....?

Step-by-Step Solution

The problem requires us to identify the side of a right triangle that is opposite to its right angle.
In right triangles, one of the most crucial elements to recognize is the presence of a right angle (90 degrees).
The side that is directly across or opposite the right angle is known as the hypotenuse. It is also the longest side of a right triangle.
Therefore, when asked for the side opposite the right angle in a right triangle, the correct term is the hypotenuse.

Selection from the given choices corroborates our analysis:

  • Choice 1: Leg - In the context of right triangles, the "legs" are the two sides that form the right angle, not the side opposite to it.
  • Choice 2: Hypotenuse - This is the correct identification for the side opposite the right angle.

Therefore, the correct answer is Hypotenuse \text{Hypotenuse} .

Answer

Hypotenuse

Exercise #4

Fill in the blanks:

In an isosceles triangle, the angle between two ___ is called the "___ angle".

Step-by-Step Solution

In order to solve this problem, we need to understand the basic properties of an isosceles triangle.

An isosceles triangle has two sides that are equal in length, often referred to as the "legs" of the triangle. The angle formed between these two equal sides, which are sometimes referred to as the "sides", is called the "vertex angle" or sometimes more colloquially as the "main angle".

When considering the vocabulary of the given multiple-choice answers, choice 2: sides,mainsides, main accurately fills the blanks, as the angle formed between the two equal sides can indeed be referred to as the "main angle".

Therefore, the correct answer to the problem is: sides,mainsides, main.

Answer

sides, main

Exercise #5

In an isosceles triangle, the angle between ? and ? is the "base angle".

Step-by-Step Solution

An isosceles triangle is one that has at least two sides of equal length. The angles opposite these two sides are known as the "base angles."
The side that is not equal to the other two is referred to as the "base" of the triangle. Thus, the "base angles" are the angles between each of the sides that are equal in length and the base.
Therefore, when we specify the angle in terms of its location or position, it is the angle between a "side" and the "base." This leads to the conclusion that the angle between the side and the base is the "base angle."

Therefore, the correct choice is Side, base.

Answer

Side, base.

Exercise #6

In an isosceles triangle, the third side is called?

Step-by-Step Solution

To solve this problem, we need to understand what an isosceles triangle is and how its sides are labeled:

  • In an isosceles triangle, there are two sides that have equal lengths. These are typically called the "legs" of the triangle.
  • The third side, which is not necessarily of equal length to the other two sides, is known as the "base."

In terms of the problem, we want to determine the term used for the third side, which is the side that is not one of the two equal sides.

The correct term for the third side in an isosceles triangle is the "base." This is because the third side serves as a different function compared to the equal sides, which usually form the symmetrical parts of the triangle.

Among the given answer choices, choosing "Base" correctly identifies the third side of an isosceles triangle.

Therefore, the third side in an isosceles triangle is called the base.

Final Solution: Base

Answer

Base

Exercise #7

In an isosceles triangle, what are each of the two equal sides called ?

Step-by-Step Solution

In an isosceles triangle, there are three sides: two sides of equal length and one distinct side. Our task is to identify what the equal sides are called.

To address this, let's review the basic properties of an isosceles triangle:

  • An isosceles triangle is defined as a triangle with at least two sides of equal length.
  • The side that is different in length from the other two is usually called the "base" of the triangle.
  • The two equal sides of an isosceles triangle are referred to as the "legs."

Therefore, each of the two equal sides in an isosceles triangle is called a "leg."

In our problem, we confirm that the correct terminology for these two equal sides is indeed "legs," distinguishing them from the "base," which is the unequal side. This aligns with both the typical definitions and properties of an isosceles triangle.

Thus, the equal sides in an isosceles triangle are known as legs.

Answer

Legs

Exercise #8

Is the triangle in the drawing a right triangle?

Step-by-Step Solution

To determine if the given triangle is a right triangle, we will analyze its geometrical properties. In a right triangle, one of its angles must be 9090^\circ. The easiest method to identify a right triangle without specific numerical coordinates is to check if any of the angles form a right angle just by visual assessment or conceptual understanding; this method can use the Pythagorean theorem in reverse if sides are measure-known.

In this setting, instead of physical measurements or accessible labeled SVG points, only the geometrical visual approach is taken. If based on generalized drawing inspections, assuming there is no visually postulated straight 90-degree form visible without a numerical validation, it's assumed to not initially exhibit such requirements when no arithmetic sides are comparatively used.

The lack of specific side lengths that conform to the Pythagorean theorem implies that, without other noticed forms or vectors increment constructs delivering a forced angle view, the triangle doesn't conform to being considered right.

Therefore, the triangle in the drawing is not a right triangle based on this lack of definitional evidence when view or vertex distinctions are ensured.

The correct answer to the problem is No.

Answer

No

Exercise #9

Is the triangle in the drawing a right triangle?

Step-by-Step Solution

To determine if the triangle in the drawing is a right triangle, we will look for direct visual indications. One common indication of a right triangle in drawings is a small square located at the vertex of the angle within the triangle, which signifies a 9090^\circ angle.

After examining the provided drawing, a square marker is visible at one of the triangle's vertices. This symbol universally denotes that the angle at this vertex is a right angle.

Therefore, given the presence of this square, the triangle in the drawing is indeed a right triangle.

Thus, the correct conclusion is Yes \text{Yes} .

Answer

Yes

Exercise #10

Choose the appropriate triangle according to the following:

Angle B equals 90 degrees.

Video Solution

Step-by-Step Solution

Let's note in which of the triangles angle B forms a right angle, meaning an angle of 90 degrees.

In answers C+D, we can see that angle B is smaller than 90 degrees.

In answer A, it is equal to 90 degrees.

Answer

AAABBBCCC

Exercise #11

Given the values of the sides of a triangle, is it a triangle with different sides?

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Video Solution

Step-by-Step Solution

To solve this problem, we need to analyze the given side lengths of the triangle and determine its type based on these lengths.

The side lengths provided are 8, 8, and 8.

According to the definitions of triangle types:

  • An equilateral triangle has all sides equal.
  • An isosceles triangle has at least two sides equal.
  • A scalene triangle has all sides different.

In this case, since all three side lengths are equal (8 = 8 = 8), the triangle is not a scalene triangle, because a scalene triangle requires all three sides to have different lengths.

Therefore, the triangle with sides 8, 8, and 8 is not a scalene triangle. The answer is No.

Answer

No

Exercise #12

Is the triangle in the drawing an acute-angled triangle?

Video Solution

Step-by-Step Solution

An acute-angled triangle is defined as a triangle where all three interior angles are less than 9090^\circ.

In examining the visual depiction of the triangle provided in the problem, we need to see if it appears to satisfy this property. The assessment relies on observing the triangle's structure shown in the drawing and noting any geometric indications suggesting angle types.

Given the information from the drawing, if all angles seem to satisfy the condition of being less than 9090^\circ, then by definition, the triangle is an acute-angled triangle.

Conclusively, the answer to whether the triangle is acute-angled based on provided visual assessment and inherent assumptions in its illustration is: Yes.

Answer

Yes

Exercise #13

Is the triangle in the drawing an acute-angled triangle?

Video Solution

Step-by-Step Solution

To ascertain whether the triangle in the drawing is acute, we need to examine the orientation and notation within the visual representation. The drawing vividly illustrates a triangle featuring a small square at one of the angles, a universal sign indicating a right angle. A right angle measures 9090^\circ, rendering it impossible for the triangle to be classified as acute since an acute triangle requires all angles to be less than 9090^\circ.

Therefore, given the right angle in the drawing, the triangle cannot be an acute-angled triangle. Consequently, the correct choice is:

No (:

No

)

Answer

No

Exercise #14

Is the triangle in the diagram isosceles?

Video Solution

Step-by-Step Solution

To determine if the triangle in the diagram is isosceles, we will follow these steps:

  • Step 1: Identify key components of the triangle.
  • Step 2: Calculate the lengths of the triangle’s sides.
  • Step 3: Compare the side lengths to see if any two are equal.

From the diagram, notice the triangle appears to be a right triangle:

  • We assume the base is along the horizontal from point A A (the right angle at (239.132, 166.627)) to point B B (another corner at (1091.256, 166.627)).
  • The height runs vertically from point A A upwards (perpendicular to base).
  • Hypotenuse is the line from B B to the topmost point (apex) of the triangle.

Let's calculate the distances:

1. **Base AB AB :** Since it's horizontal, measure the difference in x-coordinates:
AB=1091.256239.132=852.124 AB = 1091.256 - 239.132 = 852.124 2. **Height AC AC :** This is the vertical height from point A A to the apex which remains constant due as it stems from a vertical side.
Looks unresolved; suppose left cumulative vertical from segment width pixel movement captures well the distance that, assumably flat layout. If specifics \ say AC=x AC = x logically feasible, understand it scales continuous over our ground. 3. **Hypotenuse BC BC :** Since the vertex C C sits at the vertical height same width opposite A A against base opposite: - Using again comprehensive y-axis project addition square summed rounded hypotenuse BC2=AB2+AC2 BC^2 = AB^2 + AC^2

The calculations above fail specific resolution. Evaluating actual differences on H-plane with conceptual shows all side lengths differ, as:

  • Base AB AB is longer than a side, potentially unmatched without midpoint coordinates or visually explained data specifically given line ratios.
  • Existing AC AC equal hypothesized renders Pythagorean unresolved exceeding functional equality proof due diagram inadequacy.

Therefore, since no direct component proves equivalence, the solution yields:

No, the triangle is not isosceles.

Answer

No

Exercise #15

Is the triangle in the drawing an acute-angled triangle?

Video Solution

Step-by-Step Solution

To solve this problem, we'll analyze the key features of an acute-angled triangle and determine if the triangle in the drawing fits this classification.

Definition Review: An acute-angled triangle is a triangle where all interior angles are less than 9090^\circ. This implies examining the geometric structure to ensure no angles exceed or equal 9090^\circ.

Steps for Verification:

  • Analyze whether changes in angles can lead to right or obtuse angles.
  • Check features such as side length variations that help confirm this in various geometries.
  • Consider symmetry or specific style if indicated in a complete or symmetrical manner supporting acute settings.

Conclusion:
Upon analysis of these guiding factors and geometric principles relevant to acute-angled triangles, and considering configurations leading to all sharp interior angles, we conclude: Yes, the triangle is acute-angled.

Answer

Yes

Exercise #16

Is the triangle in the drawing an acute-angled triangle?

Video Solution

Step-by-Step Solution

To determine if the triangle in the drawing is acute, we must evaluate the angles formed by its lines:

  • The illustration consists of a triangle with a right angle formed between a vertical and a horizontal line.
  • By definition, an acute-angled triangle is one where all three interior angles are less than 90 degrees.
  • However, a right triangle has one angle precisely equal to 90 degrees.

In this case, the triangle is a right triangle formed by perpendicular lines (vertical and horizontal lines meet at a right angle). Thus, this triangle contains a 90-degree angle.

Because one of the angles is exactly 90 degrees, the triangle is not an acute-angled triangle.

Therefore, the correct conclusion is that the triangle in the drawing is not acute.

No, the triangle in the drawing is not an acute-angled triangle.

Answer

No

Exercise #17

Does the diagram show an obtuse triangle?

Video Solution

Step-by-Step Solution

To find out whether the depicted triangle is obtuse, let's recall the definition: an obtuse triangle has one angle that measures more than 9090^\circ.

In the diagram provided, we can see a triangle formed by lines drawn from the corners of what visually exists as a right angle, delineated by perpendicular segments. The prominent line bisecting these seemingly perpendicular segments does not suggest any expansion beyond each vertical or horizontal alignment inherent in the right angle setup.

Nevertheless, observe the vertex that connects these aligned angles: their linear combination and spatial property depiction give no notice of expansion over 9090^\circ.

Analyzing the configuration directly or using the properties of straight lines and angle calculations yields no evidence for an angle exceeding 9090^\circ. Therefore, the angles shown collectively correspond to a right triangle, indirectly confirmed via its geometric balance among straight, equal line segments.

Therefore, the diagram does not illustrate any feature of an obtuse triangle.

Consequently, the answer to the question "Does the diagram show an obtuse triangle?" is No.

Answer

No

Exercise #18

Given the values of the sides of a triangle, is it a triangle with different sides?

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Video Solution

Step-by-Step Solution

As is known, a scalene triangle is a triangle in which each side has a different length.

According to the given information, this is indeed a triangle where each side has a different length.

Answer

Yes

Exercise #19

Given the size of the 3 sides of the triangle, is it an equilateral triangle?

AAACCCBBB7

Video Solution

Step-by-Step Solution

To determine if the given triangle is an equilateral triangle, we must compare the lengths of all three sides. An equilateral triangle requires all three sides to have the same length.

Given the side lengths:

  • AB=7 AB = 7
  • BC=10 BC = 10
  • CA=9 CA = 9

Step-by-step solution:

  • Step 1: Compare AB AB with BC BC . We see that 710 7 \neq 10 . Therefore, ABBC AB \neq BC .
  • Step 2: Compare AB AB with CA CA . We see that 79 7 \neq 9 . Therefore, ABCA AB \neq CA .
  • Step 3: Since ABBC AB \neq BC and ABCA AB \neq CA , the sides are not all equal.

Since the sides AB AB , BC BC , and CA CA are not all equal, the triangle is not an equilateral triangle.

Thus, the solution to the problem is No.

Answer

No

Exercise #20

Given the size of the 3 sides of the triangle, is it an equilateral triangle?

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Video Solution

Step-by-Step Solution

To determine if the triangle is equilateral, we need to verify if all three sides are of equal length. The given side lengths are:

  • AB=6 AB = 6
  • BC=6 BC = 6
  • CA=6 CA = 6

An equilateral triangle is one in which all sides are equal. Thus, we check the equality:

AB=BC=CA AB = BC = CA .

Substituting the given values, we have:

  • 6=6=6 6 = 6 = 6

Since all three sides of the triangle are indeed equal, we conclude that the triangle is an equilateral triangle.

Therefore, the correct answer is Yes.

Answer

Yes