A curve that does not cross itself.
What is a Simple Curve?
An angle of 90°, as in a corner of a square or at the intersection of two perpendicular straight lines.
What is a right angle?
Abstract ideas illustrated by dots, corners of boxes and tips of pointed objects.
What are points?
A straight line from the center to the circumference of a circle or sphere.
What is a radius?
A device for measuring angles.
What is a protractor?
A curve that crosses itself.
What is a simple closed curve?
An angle that is less than 90 degrees.
What is an acute angle?
A set of points described intuitively as being straight and extending indefinitely in both directions.
What is a line?
A straight line passing from side to side through the center of a body or figure, especially a circle or sphere.
What is a Diameter?
The union of a simple closed curve and its interior.
What is a plane region?
A curve that has a supporting line through each of its points.
What is Convex?
An angle exceeding 90 degrees but less than 180 degrees.
What is an obtuse angle?
A flat, two-dimensional surface that extends infinitely far.
What is a plane?
The enclosing boundary of a curved geometric figure, especially a circle
What is a circumference?
1/360 of a complete turn about a circle.
What is a degree?
A curve with no endpoints and which completely encloses an area.
What is a closed curve?
An angle whose sides lie in opposite directions from the vertex.
What is a straight angle?
A half-space is either of the two parts into which a plane divides the three-dimensional Euclidean space.
What is a half-plane?
A straight line segment whose endpoints both lie on a circular arc.
What is a chord?
Two angles thats sum measures 90 degrees.
What is Complementary?
The negative or opposite of a convex.
What is concave?
An angle greater than 180° and less than 360°.
What is a reflex angle?
A part of a line that is bounded by two distinct end points, and contains every point on the line that is between its endpoints.
What is a line segment?
The line through a pair of infinitely close points on the curve.
What is a tangent?
Two angles thats sum measures 180 degrees.
What is supplementary?