What is an angle that measures less than 90° called?
Acute angle
How many sides does a pentagon have?
5
How many sides does a triangle have?
3
What is the distance from the center to the edge of a circle called?
Radius
What is symmetry?
When one half matches the other half
What type of angle is exactly 90°?
Right angle
What do you call a shape with all sides and angles equal?
Regular polygon
What is a triangle with all equal sides called?
Equilateral triangle
What is the distance all the way across a circle through the center?
Diameter
What is a line that divides a shape into two equal halves called?
Line of symmetry
What type of angle is greater than 90° but less than 180°?
Obtuse angle
Name a quadrilateral with two pairs of parallel sides.
Parallelogram
What is a triangle with one right angle called?
Right triangle
What is the name for the boundary of a circle?
Circumference
Does a rectangle have lines of symmetry? How many?
2
Two lines cross and form four angles. What are opposite angles called?
Vertical angles
What is the difference between a square and a rectangle?
A square has all equal sides; a rectangle only has opposite sides equal
The angles in a triangle always add up to what number?
180°
Fill in the blank - A _____ is a 'slice' of the circle
Sector
How many lines of symmetry does a square have?
4
If one angle in a straight line is 120°, what is the other angle?
60° (because they add to 180°)
A shape has 8 sides. What is it called?
Octagon
What are the three main types of triangles?
isosceles, equilateral, scalene
If the diameter of a circle is 12 cm, what is the radius?
6 cm
How many lines of symmetry does a scalene triangle have?
Zero