Triangles
All right angles are ________ degrees.
What is 90?
Lines that go forever in the same direction without ever intersecting.
What are parallel lines?
A radius of a circle is equal to half the length of the __________.
What is diameter?
The instrument used for making arcs in constructions.
What is a compass?
The _________ is equal to the sum of all its parts.
What is the whole?
A triangle with all sides having equal length.
A line that perfectly cuts another line into two or more equal parts.
What is a bisector?
The instrument used for drawing circles.
What is a compass?
Two geometric figures that have the same shape and size are ____________.
What is congruent?
A geometric statement that is easily deduced from a theorem.
What is a corollary?
A triangle having no two sides equal.
What is a scalene triangle?
Any two straight lines intersect to form equal __________ angles.
The arc that represents a quarter of a circle.
What is a quadrant?
A line can be bisected by but one ______.
A pre-proof planning of how to complete a proof.
A triangle which has at least two sides equal.
What is an isosceles triangle?
The sum of all the angles about a point on one side of a straight line is ________________.
What is a straight angle?
The perimeter of a circle.
What is circumference?
In two congruent figures, the equal parts are called _______________ parts.
What are corresponding parts?
The process of reasoning that establishes the truth of a theorem or the correctness of a construction.
What is a proof?
A triangle which has three equal angles.
What is an equiangular triangle?
A line segment is divided into three equal parts by two points called the __________________.
What are trisection points?
Any straight line whose ends are on the circle.
What is a chord?
Added lines in a diagram used to aid in solving proofs are called _________ lines.
What are auxiliary lines?
A geometric statement that is accepted without proof to be true.
What is a postulate?