Geometry

Quadrilateral Related Stuff:

area of a parallelogram

area of a trapezium

Triangle Related Stuff:

angles in a triangle add up to 180 degrees

constructing an equilateral triangle

area of a triangle

pythagoras theorem

sides of a 30-60-90 triangle

Circle Related Stuff:

thales theorem

More Quadrilateral Related Stuff:

constructing a parallelogram with a given angle and with an area equal to a given triangle

Conic Sections:

getting the standard form equation of a parabola from the focus and directrix definition

axis of symmetry of a parabola

vertex form equation of a parabola

getting the focus, directrix and the vertex of a parabola from y = ax2 + bx + c

the reflective property of a parabola

the equivalence of the focus-directrix definition and the conic section definition of a parabola