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Mid points of sides of a triangle are (1/2,0) , (0,1/2) , (12,1/2) then circum centre of triangle is |
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Answer» Answer Let A(x 1
,y 1
),B(x 2
,y 2
),C(x 3
,y 3
) be the vertices of △ABC Let D(2,1) , F(-1,-3) and E(4,5) be the mid points of AB,AC and BC. D and F are mid points PF ABC and AC ∴DF∥BE E and F are mid points pf BC and Ac ∴EF∥BD ∴ DBEF is a PARALLELOGRAM. The diagonals of a parallelogram bisect each other i.e, both diagonals have same mid POINT i.e, Midpoint BF=Midpoint of DE ( 2 x 2
+(−1)
, 2 y 2
+(−3)
)=( 2 2+4
, 2 1+5
) ∴ 2 x 2
+(−1)
= 2 2+4
∴x 2
=7 Similarly 2 y 2
+(−3)
= 2 1+5
∴y 2
=9 i.e,(x 2
,y 2
)=(7,9) D is the mid point of AB D=(2,1)=( 2 x 1
+x 2
, 2 y 1
+y 2
) 2 x 1
+7
=2∴x 1
=−3 i.e,(x 1
,y 1
)=(−3,−7) 2 y 1
+9
=1∴y 1
=−7 F is the midpoint of AC F=(−1,−3)=( 2 x 1
+x 3
, 2 y 1
+y 3
) −1= 2 −3+x 3
∴x 3
=1 i.e,(x 3
,y 3
)=(1,1) −3= 2 −7+y 3
∴y 3
=1 ∴ The vertices of triangle are =(−3,−7),(7,9),(1,1) |
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