Common Notion Potion
"Things which are equal to the same thing are also equal to one another"
What is C.N. 1?
Prop. I.6
What is "If in a triangle two angles be equal to one another, the sides which subtend the equal angles will also be equal to one another"?
The geometric word that means "to cut something into two equal pieces."
What is "bisect"?
"To describe a circle with any center and distance."
What is Post. 3?
This word literally means "straight line" in geometry.
What is "rectilinear"?
"The whole is greater than the part."
What is C.N. 5?
This Proposition is nicknamed Side-Angle-Side (SAS).
What is Prop. I.4?
We say two figure are ___________ when their respective sides and angles are equal.
What is "congruent"?
Post. 1
What is "to draw a straight line from any point to any point"?
A triangle that is non-equilateral and non-isosceles.
What is a "scalene" triangle?
Common Notion 4
What is "Things which coincide with one another are equal to one another"?
Prop. I.5
What is "In isosceles triangles the angles at the base are equal to one another, and, if the equal straight lines be produced further, the angles under the base will be equal to one another"?
We say the side opposite an angle in a triangle _________ the angle.
What is "subtends"?
Post. 4
What is "All right angles are equal to one another"?
Define a figure (Defn. 14).
What is "that which is contained by any boundary or boundaries"?
"If equals be subtracted from equals, the remainders are equal."
What is C.N. 3?
Prop. I.8
What is "If two triangles have two pairs of sides equal respectively, and with equal bases, then the angles opposite the bases will be equal (and the triangles will be congruent)"?
The word for the ends or edges of a geometric figure/surface.
What is an "extremity"?
"To produce a finite straight line continuously in a straight line."
What is Post. 2?
Define parallel straight lines (Defn. 23).
What is "straight lines which, being in the same plane and being produced indefinitely in both directions, do not meet one another in either direction"?
Common Notion 2
What is "If equals be added to equals, the remainders are equal"?
"Given two straight lines constructed on a straight line [from its extremities] and meeting in a point, there cannot be constructed on the same straight line [from its extremities], and on the same side of it, two other straight lines meeting in another point and equal to the former two respectively, namely each to that which has the same extremity with it."
What is Prop. I.7?
Perpendicular lines form these kinds of angles.
What are "right angles"?
Draw and explain Post. 5
Define a Rhombus (Defn. 22).
What is "a quadrilateral which is equilateral but not right-angled"?