Unit 1 Flashcards
How do you name a point?
With a single capital letter
How do you define a plane?
By 3 noncollinear points
What are the ways to name a plane?
With 3 noncollinear points or a script capital letter
Two or more points that lie in the same line are called what?
Collinear
Three or more points that lie in the same plane are called what?
Coplanar
If you draw 3 points that are noncollinear, how many planes go through those points?
One
If you draw 2 points, how many planes pass through them?
Infinite
What is formed by the intersection of 2 planes?
A line
What is formed by the intersection of 2 lines?
A point
How do you name a line?
- With any 2 points and the symbol for line above it
- With a lowercase letter (no symbol)
How do you name a line segment?
Line Segment: With the 2 endpoints and the line symbol above it
How do you name a ray?
Ray: With the endpoint first, followed by another point on the ray, with the ray symbol above it
What do opposite rays look like?
A line
If you draw 2 opposite rays, what do they have in common?
The endpoint
What are 2 congruent segments?
2 segments with the same length
On a number line what is the coordinate, the number or the letter?
The number
How do you find the length of a segment on a number line?
The absolute value of the difference of the coordinates
What does midpoint mean?
Point in the middle of a line segment creating 2 congruent segments
What is the midpoint formula on a number line?
M = (A+B)/2
What is the difference between definition of midpoint and the midpoint theorem?
Definition compares the 2 smaller segments. Theorem compares smaller to larger segment
What is a segment bisector?
A line ray or segment that cuts a segment in half
Where is a vertex of an angle?
Where the sides intersect
What are 3 ways to name an angle? What is the catch to two of those methods?
- 3 letter method - vertex must be second
- Little number method
- Vertex only method - only if one angle has that vertex
How do we measure an angle?
In degrees
What is the smallest and largest possible measure for an angle?
Greater than 0º but less than 180º
What is an acute angle?
An angle with measure less than 90º
What is an obtuse angle?
An angle with measure greater than 90°
What is a right angle?
An angle with measure equal to 90°
What are congruent angles?
2 angles with the same measure (the same number of degrees)
What is the rule involving right angles? (word for word)
All right angles are congruent
What are adjacent angles?
Two angles that share a common vertex, share a common side, and do not overlap
What is an angle bisector?
A ray that divides an angle in half creating 2 congruent angles
What is the difference between the definition of angle bisector and the angle bisector theorem?
The definition compares smaller angle to smaller angle. The theorem compares smaller angle to larger angle
What are vertical angles?
The opposite angles formed by two intersecting lines
What is the rule with vertical angles? (word for word)
Vertical angles are congruent
What is the definition of complementary angles?
2 angles whose measures add up to 90º.
Can complementary angles be adjacent?
Yes
What is the definition of supplementary angles?
2 angles whose measures add up to 180º.
Can supplementary angles be adjacent?
Yes
What do we call 2 adjacent supplementary angles?
A linear pair
So the rule for linear pair is if two angles form a linear pair, then they are_____?
Supplementary
What are the 4 steps when you see a variable (x)?
- Set up an equation
- Solve the equation
- Substitute in for variable
- Answer the question
If the measure of an angle is x°, what is the measure of its complement?
measure of the complement: 90 – x
If the measure of an angle is x°, what is the measure of its supplement?
measure of the supplement: 180 – x
What is the difference between supplementary and a linear pair?
A linear pair must be adjacent, while supplementary angles do not have to be adjacent
What should you mark whenever you have a midpoint?
Congruent segments
What should you mark whenever you have a segment bisector?
Congruent segments
What should you mark whenever you have an angle bisector?
Congruent angles
What should you mark whenever you have vertical angles?
Congruent angles
