geometric shapes (plane figures)
Types of triangle
All the sides are the same length and all the angles are equal.
Two sides are of the same length and two angles are of equal size.
All sides are different lengths and all the angles are of different sizes.
A triangle with three acute angles, each less than 90°.
A triangle containing one right angle (90°).
A triangle containing one obtuse angle (over 90°).
Types of quadrilateral
All the sides are the same length and all the angles are right angles.
Opposite sides are the same length and all angles are right angles.
All sides are the same length but none of the angles are right ngles.
Opposite sides are parallel to each other and of the same length.
One pair of the opposite sides is parallel.
Adjacent sides are equal length and the diagonals intersect at right angles.
Pythagoras' theorem: a2 = b2+c2
1 = 3.1415926 (recurring) r = radius
Parallelogram (l = length, h = perpendicular distance to side parallel to l)
Rectangle (l = length, w = width)
Cone (h = perpendicular height)
Pyramid (B = area of base)