This question is incomplete, the complete part of the question containing the students definition and teacher's comment is:
Ruby's definiton: A 3-dimensional shape whose boundary consists of all points equidistant from a fixed point (the center).
Shriya's definition: The set of all points in a 2D plane such that for every point in the set there is exactly one other point in the set that is d (call it diameter) units away.
Abhishek's definition: The set of all points in a plane that are the same distance (radius) away from some given point (center).
Teacher's comments:
Are you thinking of a sphere?
You are correct. Nicely done!
This is incorrect. For example, your definition also allows for the following shape, which is just part of a circle.
THE ANSWERS ARE:
Ruby's definiton: Are you thinking of a sphere?
Shriya's definition: This is incorrect. For example, your definition also allows for the following shape, which is just part of a circle.
Abhishek's definition: You are correct. Nicely done!
Explanation:
A circle is a two-dimensional round plane shape (2D shape) whose boundary line called the circumference has several points that are of the same distance (radius) from the centre point of the shape.
Based on this definition of a circle, the answers given by each students will now be reviewed.
1). Ruby's definiton: This definition is wrong because a circle is not a 3D shape. The definition is describing more of a SPHERE, which is a 3D round shape in a space. Hence, the teachers comment will appropriately be; Are you thinking of a sphere?
2.) Shriya's definition: This definition is wrong because it is not describing a circle, rather it is describing a part of a circle (diameter). Hence, the teachers comment appropriate for this answer is: This is incorrect. For example, your definition also allows for the following shape, which is just part of a circle
3). Abhishek's definition: This definition correctly describes a circle, hence, the teacher's comment will be: You are correct. Nicely done!
