Two sides of a triangle are $7\text{ cm}$ and $10\text{ cm}$, and their included angle is \(120^

Question

Two sides of a triangle are $7\text{ cm}$ and $10\text{ cm}$, and their included angle is $120^\circ$. Find the third side to $3\text{ s.f.}$[3]

Accepted Answer

$14.8\text{ cm}$ (3 s.f.)

Trigonometry