Question

PLS HELP ASAP

Answer 1

Correct answer is : Area of triangle is $15\sqrt{3} sq.units$

Solution:-

We can do it in 2 methods.

Method 1:-

Given that AB=6, BC=10 and m∠B = 120

Then area of triangle = $\frac{1}{2}XbaseXheight$

Let us assume AB is base and D is an altitude from C onto AB.

Then sin(60)= $\frac{CD}{BC}$

          CD = BC sin(60)

Hence height = $10*\frac{\sqrt{3}}{2}$ = $5\sqrt{3}$

Hence area of ΔABC = $\frac{1}{2} X6X5\sqrt{3} = 15\sqrt{3}$ sq.units

Method2:-

Area of triangle = $\frac{1}{2} acsin(B)$

Here a= BC=10, c=AB=6.

Hence area of triangle = $\frac{1}{2}X6X10sin(120) = 15\sqrt{3}$ sq.units