Important Formulas

You should know these formulas by heart.

Some of these have different versions floating around.

I strongly recommend you use these versions.

Areas of Shapes

Area of a Triangle

$$ A = \frac{b × h}{2} $$

Area of a Trapezium

$$ A = \frac{a + b}{2} × h $$

Area of a Circle

$$ A = \pi r^2 $$

Circumference of a Circle

$$ C = \pi D $$

Pythagoras’ Theorem

$$ a^2 + b^2 = c^2 $$

The Quadratic Formula

$$x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$$