Question

Given: △ABC, m∠B=120° AB=6, BC=10 Find: Area of △ABC

Answer 1

In the triangle two sides and measure of included angle is given.This is also called side angle side .The area of triangle with sides a and b with included angle C is given by:

Area = $\frac{absinC}{2}$

Or Area of triangle = $\frac{ (AB)(BC)sinB}{2}$

Substituting the given values :

Area of triangle =$\frac{(6)(10)sin120}{2}$

Area of triangle = 30 sin 120

Area of triangle = 25.98 square units