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Grade 11Analytical Geometry

Prove:(2,-2),(8,4),(5,7)&(-1,1) are the angular points of a rectangle

Profile image of Alisha
8 Years agoGrade 11
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1 Answer

Profile image of Arun
8 Years ago
Let these points are A,B,C,D respectively.
Hence
From distance formula
distance AB =52^(1/2)
distance CD = 52 ^(1/2)
distance BC = 18^(1/2)
distance AD = 18^(1/2)
Now AB = CD & BC = AD
One property of rectangle is that its disgonal are equal in length.
Now 
length AC = 90^(1/2)
length BD = 90^(1/2)
Now AC = BD also.
Hence this is a rectangle