A triangle has two corners with angles of π2 and π6. If one side of the triangle has a length of 5, what is the largest possible area of the triangle?

1 Answer
Feb 27, 2017

The largest possible area is 21.65.

Explanation:

As the two angles are π2 and π6, the third angle is

ππ2π6=6π63π6π6=6π3ππ6=2π6=π3

As the smallest angle of the three is π6,

area will be largest if side with length 5 is opposite the smallest angle π6

Such a triangle is typical 306090 triangle and looks like as shown below

enter image source here

In such a right angled triangle, if smallest side is 5, hypotenuse is 5×2=10 and third side 5×3.

As the two sides forming the right angle in right angled triangle are 5 and 53, the area of triangle is

12×5×53=252×1.732=21.65 and

The largest possible area is 21.65.