Triangles
What are 2 ways to classify triangles?
by sides and by angles
How many sides does a quadrilateral have?
4
How many endpoints does a ray have?
1
What is the plural of radius?
Radii
What is an acute angle?
an angle less that 90 degrees
What is the name of a triangle that has 3 equal sides?
equilateral
True or False: A square is a type of rectangle
True
What kind of angles do perpendicular lines form?
right angles (or 90 degree angles)
What is the line that goes from the centerpoint of a circle to the edge?
Radius
What shape fits perfectly into a right angle?
square
What do you call a triangle with exactly 2 equal sides?
isosceles
How many pairs of parallel lines does a parallelogram have?
2 pairs
Finish these song lyrics: Parallel, intersecting, ...
perpendicular, it's rectangular
If you know the length of a radius, how do you find the diameter?
Double it
How many angles are there in a pentagon?
5
What is a scalene triangle?
a triangle with three different sides
Name 3 things that a shape needs in order to be considered a rectangle
opposite sides are equal, 4 right angles, opposite sides are parallel
How can you tell if 2 lines are parallel or intersecting if they are not touching?
Continue the lines with your fingers, a pencil, or your imagination and see if they will crooss further down in either direction
What is a diameter?
a line that cuts through the centerpoint of a circle and goes from one side to the other
What do you call an angle larger that a right angle?
obtuse
How many obtuse angles can you have in a triangle?
only one
What do you call a shape with exactly one pair of parallel sides?
trapezoid
Can 5 lines be parallel?
yes
True or false: A radius is one-half the length of a diameter
True
What is the angle measurement of a straight line?
180 degrees