A triangle with all three sides of equal length. All angles are 60 degrees.
What is an equilateral triangle?
100
A 4-sided flat shape with straight sides where all interior angles are right angles. Also, opposite sides are parallel and of equal length.
What is a rectangle?
100
A 6-sided shape.
What is a hexagon?
100
A 5-sided shape.
What is a pentagon?
100
When one shape becomes exactly like another if you flip, slide, or turn it. A reflection is the simplest form of this.
What is symmetry?
200
A triangle that has all angles less than 90 degrees.
What is an acute triangle?
200
A 4-sided flat shape with straight sides where opposite sides are parallel. Also, opposite sides are equal and opposite angles are equal. Squares, rectangles, and rhombuses are all this shape.
What is a parallelogram?
200
An 8-sided shape.
What is an octagon?
200
If all sides and all angles are equal, then it is this type of polygon.
What is a regular polygon?
200
When two lines on a plane never meet. They are always the same distance apart.
What is parallel?
300
A triangle that has an angle greater than 90 degrees.
What is an obtuse triangle?
300
A 4-sided flat shape with straight sides where all sides have equal length. Opposite sides are parallel and opposite angles are equal. It is a type of parallelogram.
What is a rhombus?
300
A 7-sided shape.
What is a heptagon?
300
A 4 sided shape with straight sides where all sides have equal length and every angle is a right angle. It is a quadrilateral and a regular polygon.
What is a square?
300
The same shape and size. Two shapes are this if you can turn, flip, or slide one and it fits exactly on the other.
What is congruent?
400
A triangle with all sides of different lengths. No sides or angles are equal.
What is a scalene triangle?
400
A 4-sided flat shape with straight sides that has a pair of opposite sides parallel.
What is a trapezoid?
400
A 10-sided shape.
What is a decagon?
400
A flat shape with four straight sides.
What is a quadrilateral?
400
Lines that are at right angles to each other.
What is perpendicular?
500
A triangle with two equal sides. The angles opposite the equal angles are also equal.
What is an isosceles triangle?
500
A 4-sided flat shape with straight sides that has 2 pairs of sides. Each pair is adjacent sides (they meet) that are equal in length. Also, the angles are equal where the pairs meet. Diagonals meet at right angles, and one of the diagonals bisects (cuts equally in half) the other.
What is a kite?
500
A 9-sided shape.
What is a nonagon?
500
This is when two shapes are only different in size (and possibly the need to turn or flip one around).
What are similar shapes?
500
A two-dimensional shape with straight sides. No curves allowed.