A right triangle is a triangle that has oneright 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).
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.
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Question 1
What kind of triangle is given in the drawing?
Incorrect
Correct Answer:
Isosceles triangle
Question 2
What kid of triangle is the following
Incorrect
Correct Answer:
Obtuse Triangle
Question 3
What kind of triangle is given in the drawing?
Incorrect
Correct Answer:
Isosceles triangle
Examples with solutions for Types of Triangles
Exercise #1
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 90∘.
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 90∘, 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 #2
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 #3
What kind of triangle is given in the drawing?
Video Solution
Step-by-Step Solution
As all the angles of a triangle are less than 90° and the sum of the angles of a triangle equals 180°:
70+70+40=180
The triangle is isosceles.
Answer
Isosceles triangle
Exercise #4
Given the values of the sides of a triangle, is it a triangle with different sides?
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 #5
Which kind of triangle is given in the drawing?
Video Solution
Step-by-Step Solution
As we know that sides AB, BC, and CA are all equal to 6,
All are equal to each other and, therefore, the triangle is equilateral.