A triangle has corners at (7 ,7 )(7,7), (1 ,3 )(1,3), and (6 ,5 )(6,5). What is the area of the triangle's circumscribed circle?

1 Answer

Area of the circum circle is 158.503158.503

Explanation:

Midpoint of corners (7,7) and (1,3)(7,7)and(1,3) is given by
((7+3)/2,(7+1)/2)(7+32,7+12)
= (5,4)=(5,4)
Slope of the line between the corners (7,7) and (1,3)(7,7)and(1,3) is given by
(3-7)/(1-7)3717
=(-4)/(-6)=46
=2/3=23
Slope of the perpendicular bisector for the line between the corners (7,7) and (1,3)(7,7)and(1,3) is given by
=-1/(2/3)=123
=-3/2=32
We have the equation of the perpendicular bisector for the line between the corners (7,7) and (1,3)(7,7)and(1,3) given by
Point (5,4)(5,4)
Slope -3/232
point slope form is
(y-4)/(x-5)=-3/2y4x5=32

Midpoint of corners (1,3) and (6,5)(1,3)and(6,5) is given by
((1+6)/2,(3+5)/2)(1+62,3+52)
= (3.5,4)=(3.5,4)
Slope of the line between the corners (1,3) and (6,5)(1,3)and(6,5) is given by
(5-3)/(6-1)5361
=(2)/(5)=25
=2/5=25
Slope of the perpendicular bisector for the line between the corners (1,3) and (6,5)(1,3)and(6,5) is given by
=-1/(2/5)=125
=-5/2=52
We have the equation of the perpendicular bisector for the line between the corners (1,3) and (6,5)(1,3)and(6,5) given by
Point (3.5,4)(3.5,4)
Slope -5/252
point slope form is
(y-4)/(x-3.5)=-5/2y4x3.5=52

Solving for the center of the circumcircle
(y-4)/(x-5)=-3/2y4x5=32
2(y-4)=-3(x-5)2(y4)=3(x5)
2y-8=-3x+152y8=3x+15
2y+3x-15-8=02y+3x158=0
3x+2y-23=03x+2y23=0

(y-4)/(x-3.5)=-5/2y4x3.5=52
2(y-4)=-5(x-3.5)2(y4)=5(x3.5)
2(y-4)+5(x-3.5)=02(y4)+5(x3.5)=0
2y-8+5x-17.5=02y8+5x17.5=0
5x+2y-24.5=05x+2y24.5=0

We have,
3x+2y-23=03x+2y23=0
5x+2y-24.5=05x+2y24.5=0
Eliminating y
3x-5x-23+24.5=03x5x23+24.5=0
-2x+1.5=02x+1.5=0
2x=1.52x=1.5
x=0.75x=0.75
Substituting
3(0.75)+2y-23=03(0.75)+2y23=0
2.25+2y-23=02.25+2y23=0
Simplifying
2y=23-2.252y=232.25
2y=20.752y=20.75
y=10.375y=10.375
Center for the circum circle has the coordinates
(0.75,10.375)(0.75,10.375)
Radius r=distance from center to vertex
(0.75,10.375)----(7,7)(0.75,10.375)(7,7)
Area of the circum circle is
A = pir^2A=πr2
pi=3.141π=3.141
r^2=(7-0.75)^2+(7-10.375)^2r2=(70.75)2+(710.375)2
r^2=(6.25)^2+(-3.375)^2r2=(6.25)2+(3.375)2
r^2=50.453r2=50.453
Hence, Area is
A=3.141*50.453A=3.14150.453
Area of the circum circle is 158.503158.503