Definitions [5]
Give a definition of the following term. Are there other terms that need to be defined first? What are they, and how might you define them?
parallel lines
If the perpendicular distance between two lines is always constant, then these are called parallel lines. In other words, the lines which never intersect each other are called parallel lines.
To define parallel lines, we must know about the points, lines, and the distance between the lines and the point of intersection.
Give a definition of the following term. Are there other terms that need to be defined first? What are they, and how might you define them?
line segment
Yes, we need to understand terms like point, line, ray, angle, plane, circle, and quadrilateral before defining the required terms.
A line segment is a part of a line with a definite length and two end points. In the figure, a line segment has end points A and B. It is written as `bar(AB)` or `bar(BA)`.
Give a definition of the following term. Are there other terms that need to be defined first? What are they, and how might you define them?
perpendicular lines
Yes, we need to understand terms like point, line, ray, angle, plane, circle, and quadrilateral before defining the required terms.
Two lines in the same plane, p and q, are considered perpendicular if they make a right angle and are written as p ⊥ q.
Give a definition of the following term. Are there other terms that need to be defined first? What are they, and how might you define them?
radius of a circle
Yes, we need to understand terms like point, line, ray, angle, plane, circle, and quadrilateral before defining the required terms.
The distance from the centre to a point on the circle is called the radius of the circle. In the figure, p is the centre, Q is a point on the circle, and PQ is the radius.
Give a definition of the following term. Are there other terms that need to be defined first? What are they, and how might you define them?
square
A square is a quadrilateral having all sides of equal length and all angles of the same measure, i.e.,90°. We must know about quadrilateral, side, and angle to define a square.
