A triangle has corners at (6 ,4 ), (7 ,6 ), and (3 ,8 ). What is the area of the triangle's circumscribed circle?

1 Answer
Feb 2, 2018

Area of triangle's circumscribed circle is 19.63 sq.unit.

Explanation:

Vertices of triangle are A(6,4), B(7,6) , (3,8)

Side AB=a=sqrt((6-7)^2+(4-6)^2)=sqrt5 ~~2.24

Side BC=b=sqrt((7-3)^2+(6-8)^2)= sqrt20 ~~ 4.47

Side CA=c=sqrt((3-6)^2+(8-4)^2)=sqrt 25 = 5.0

Semi perimeter of triangle S=(2.24+4.47+5.0)/2=5.855

Area of the triangle A_t=sqrt(s(s-a)(s-b)(s-c))

=sqrt(5.555(5.855-2.24)(5.855-4.47)(5.855-5.0))

= sqrt25.06 ~~5.0 sq.unit.

Circumscribed circle radius is R=(a*b*c)/(4.A_t)

R=(2.24*4.47*5.0)/(4*5.0) ~~ 2.5 unit

Area of circumscribed circle is A_c =pi*R^2=pi*2.5^2~~19.63.

Area of circumscribed circle is 19.63 sq.unit. [Ans]