Algebra 1 - lessons 1-4 Flashcards
What is a mixed number?
The sum of a whole number and a fraction
What is a mathematical line?
A straight line with no width or ends
What is a line segment?
A part of a line
When 2 lines cross, they…?
Intersect
What is the point where the 2 lines intersect called?
Point of intersection
What do we call 2 lines that are in the same plane and don’t intersect?
Parallel lines
What are the lines that make square corners at the intersection point called?
Perpendicular lines
What are the angles made by perpendicular lines called?
Right angles
What do 2 right angles form?
A straight angle.
What is an angle smaller than a right angle called?
Acute angle
What is an angle larger than a right angle called?
Obtuse angle
What is a polygon?
Simple, closed, flat geometric figure whose sides are line segments
A polygon’s sides are always equal to the number of its…?
Vertices
What do you call a polygon with an indentation?
Concave polygon
What do you call a polygon without an indentation?
Convex polygon
What do you call a polygon whose sides all have the same length?
Equilateral polygon
What do you call a polygon whose angles all have the same measure?
Equiangular polygon
What do you call polygons in which both all sides have the same length and all angles have the same measure?
Regular polygon
What are tick marks used for?
They show which sides have equal length and which angles have equal measure
How many degrees do all three-angled triangles have when the angles add up?
180 degrees
What do you call a triangle with a right angle?
Right triangle
What do you call a triangle with each of its angles being less than 90 degrees?
Acute triangle
What do you call a triangle with an angle that’s more than 90 degrees?
Obtuse triangle
What do you call a triangle with all of its angles having equal measure?
Equiangular triangle
What do you call a triangle with 2 sides of equal length?
Isosceles triangle
What do you call a triangle where all its sides have equal length?
Equilateral triangle