Right Triangle

🏆Practice types of triangles

Definition of a right triangle

A right triangle is a triangle that has one right angle, meaning an angle of 90 degrees. Based on the fact that the sum of angles in any triangle is 180 degrees, we can conclude that the sum of the two remaining angles in a right triangle is 90 degrees. This means that both angles must be acute (less than 90 degrees).

Right Triangle

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Test yourself on types of triangles!

Choose the appropriate triangle according to the following:

Angle B equals 90 degrees.

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Here are some examples of right triangles:

Examples of right triangles

Exercise

For example, let's take any right triangle. It is known that one of the angles in this triangle is 45 degrees. We are asked to find the second acute angle in the given triangle.

Since this is a right triangle, meaning one of the angles equals 90 degrees, we can calculate and find that the second acute angle will be equal to 45 degrees. Why? Because it complements the first given acute angle to 90 degrees.

Diagram of a right triangle labeled with angles: B = 90°, C = 45°, and A = ?. The triangle illustrates a problem-solving exercise to determine the missing angle A using the triangle sum theorem. Featured in a tutorial on understanding angles in a right triangle.

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Examples with solutions for Types of Triangles

Exercise #1

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 #2

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

888888AAABBBCCC8

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 #3

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 #4

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 #5

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

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