Area of triangle

To be able to calculate the area of a triangle, you need to know two sides and the included angle.

\[Area = \frac{1}{2} ab \sin C\]

Example

Find the area of triangle ABC.

Diagram of triangle with 35° angle and values 3cm and 7cm

\[Area = \frac{1}{2} \times bc \times \sin A\]

\[Area = 0.5 \times 3 \times 7 \times \sin (35^\circ )\]

\[Area = 6.02255...\]

\[Area = 6.02c{m^2}(to\,2\,d.p.)\]