Geometric Reasoning
An educated guess
Conjecture
Lines that never cross and look like railroad tracks
Parallel
The kind of angles between the two lines that are crossed.
Interior angles
What we know about the measure of vertical angles
They are equal (congruent)
It's the sum of the 3 angles in a triangle.
180
The form of a conditional that uses the phrase "if and only if"
Biconditional
Lines that cross at a 90 degree angle
Perpendicular
The name we call the line that crosses two or more other lines.
Transversal
What we know about the measures of the angles in a linear pair.
They are supplementary (add up to be 180 degrees)
Its the name of a triangle with 2 congruent sides
Isosceles
The part of the conditional statement after the word "then"
What we call lines that do not cross but are also not parallel.
Skew
Angles that are between the lines that are on opposite sides of the transversals
What a bisector does to an angle or a segment.
Cuts it in half
It's the measure of each of the 3 angles in an equilateral triangle.
60
This proves a conjecture is wrong.
Counterexample
What we call a line that crosses 2 or more other lines
Transversal
The angle pair that is supplementary when a transversal crosses parallel lines.
Same side interior (or consecutive interior)
The area of a square with a perimeter of 12m
9 or 9 meters squared
What we call the two congruent angles in an isosceles triangle
base or
base angles
These are always biconditional.
Definition
Lines that are on the same plane together.
Coplanar lines
Angles that are in the same position when a transversal crosses two or more other lines.
Corresponding
The area (in terms of pi) of a circle with a diameter of 10 cm
10 pi or
10 pi centimeters squared
The supplement of angle A is 70 degrees. What is the measure of angle A
110