SOLUTION: show that the points (-3,1), (3, -1), (1,3) are the vertices of an isosceles triangle. Find its Area

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Question 1008657: show that the points (-3,1), (3, -1), (1,3) are the vertices of an isosceles triangle. Find its Area
Answer by wynger566(1) About Me  (Show Source):
You can put this solution on YOUR website!
Let, A(-3,1), B(3,-1) and C(1,3) be the given points.
Using distance formula;
d=√[(x2-x1)^2+(y2-y1)^2]…we get
AB=√40
BC=√20 units and
AC=√20 units
Clearly BC=AC. Hence, ABC is an isosceles triangle.
For area '
From C drop perpendicular to AB then
a name it as D
Using mid point formula;
we get D= (0,0)-------> origin
also length of CD is √10 units
Finally area=1/2 AB.CD=1/2 √40 .√10 =10 sq. units