Definitions
A circle is a plane figure contained by one line such that all the lines falling on it from one point inside are equal.
To describe a circle with any center and distance.
What is "Post. 3"?
Things which coincide with one another are equal to one another.
What is "C.N. 4"?
If given a finite straight line, then we can cut it into two equal line segments (or bisect it).
What is "Prop. 10"?
If two triangles have two corresponding pairs of sides equal, and their bases are also equal, then the angles opposite the bases will be equal (and the triangles will be congruent).
What is "Prop. 8"?
A trilateral figure that has three of its sides equal is called equilateral, and one that has two of its sides equal is called isosceles, and one that has no sides equal is called scalene.
What is "Defn. 20"?
To draw a straight line from any point to any point.
What is "Post. 1"?
If equals be added to equals, the wholes are equal.
What is "C.N. 2"?
If given two unequal lines, then we can cut off the length of the shorter line from the longer line.
What is "Prop. 3"?
If given a rectilinear angle, then we can cut it into two equal angles (or bisect it).
What is "Prop. 9"?
The extremities of a line are points.
What is "Defn. 3"?
That all right angles are equal to one another.
What is "Post. 4"?
The whole is greater than the part.
What is "C.N. 5"?
What is "Prop. 7"?
If given an isosceles triangles, then the base angles are equal, and if the equal sides of the triangle are extended below the triangle, then the angles under the base are equal.
What is "Prop. 5"?
A straight line on a straight line makes the adjacent angles equal to one another, called right angles, and the lines are called perpendicular.
What is "Defn. 10"?
If a straight line falling on two straight lines makes the interior angles on the same side less than two right angles, then the two straight lines, if produced indefinitely, meet on that side on which are the angles less than two right angles.
What is "Post. 5"?
Things which are equal to the same thing are also equal to one another.
What is "C.N. 1"?
If two triangles have pairs of corresponding sides equal, and the corresponding angles between those sides are also equal, then the triangles are congruent.
What is "Prop. 4"?
If given a straight line and point on it, then we can construct another line on that point perpendicular to the first line.
What is "Prop. 11"?
Parallel lines are straight lines which, lying in the same plane and being produced indefinitely in both directions, do not meet one another.
What is "Defn. 23"?
To produce a finite straight line continuously in a straight line.
What is "Post. 2"?
If equals be subtracted from equals, the remainders are equal.
What is "C.N. 3"?
If given an infinite straight line and a point not on that line, then we can draw another line perpendicular to the first line through the point.
What is "Prop. 12"?
If the base angles of a triangle are equal, then the sides subtending them will be equal.
What is "Prop. 6"?