Point.
<h3>Further explanation</h3>
- This is one of the classic problems of Euclidean geometry.
- The angle is determined by three points, we call it A, B, C, with A ≠ C and B ≠ C.
- We express an angle with three points and a symbol ∠. The middle point represents constantly vertex. We can, besides, give angle names only with vertices. For example, based on the accompanying image, the angle can be symbolized as ∠BAC, or ∠CAB, or ∠A.
Types of Angles
- The acute angle represents an angle whose measure is greater than 0° and less than 90°.
- The right angle is an angle that measures 90° precisely.
- The obtuse angle represents an angle whose measures greater than 90° and less than 180°.
- The straight angle is a line that goes infinitely in both directions and measures 180°. Carefully differentiate from rays that only runs in one direction.
<u>Note:</u>
Undefined terms are the basic figure that is undefined in terms of other figures. The undefined terms (or primitive terms) in geometry are a point, line, and plane.
These key terms cannot be mathematically defined using other known words.
- A point represents a location and has no dimension (size). It is marked with a capital letter and a dot.
- A line represent an infinite number of points extending in opposite directions that have only one dimension. It has one dimension. It is a straight path and no thickness.
- A plane represents a planar surface that contains many points and lines. A plane extends infinitely in all four directions. It is two-dimensional. Three noncollinear points determine a plane, as there is exactly one plane that can go through these points.
<h3>Learn more
</h3>
- Undefined terms are implemented to define a ray brainly.com/question/1087090
- Definition of the line segment brainly.com/question/909890
- What are three collinear points on a line? brainly.com/question/5795008
Keywords: the definition of an angle, the undefined term, line, point, line, plane, ray, endpoint, acute, obtuse, right, straight, Euclidean geometry
The answer is D:10 cm, I just took it and got this.
Answer:
B
Step-by-step explanation:
A. these simply to 21 + 7x and 21 + 3x
- this one is incorrect because the 7x and 3x are different
B. these simplify to 10 + x and 10 + x
- this is the correct one since they are exactly the same
C. these simplify to 21x and 7x + 21
- these two are not the same because one expression has only a number with a variable but the other one has a number with a variable <em>and </em>another number
D. these simplify to
and 
- in subtraction, the order of the 3 and the x matters, so the equations are not the same
- example: 6 - 4 = 2 but 4 - 6 = -2