SOLUTION: Assignment: Proove the points A(6,-13) B(-2,2) C(13,10) and D (21, -5) are the vertices of the square. Show that the diagonals bisect each other and of equal length. Please ha

Algebra ->  Geometry-proofs -> SOLUTION: Assignment: Proove the points A(6,-13) B(-2,2) C(13,10) and D (21, -5) are the vertices of the square. Show that the diagonals bisect each other and of equal length. Please ha      Log On


   



Question 490711: Assignment:
Proove the points A(6,-13) B(-2,2) C(13,10) and D (21, -5) are the vertices of the square. Show that the diagonals bisect each other and of equal length. Please have a plan of what you're going to do before proceeding into solving the problem.
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Hello! How am I going to solve this problem? Am I going to get their distances and midpoints? Please help me. Thank you :)

Found 2 solutions by richard1234, josmiceli:
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
First, you can show that AB, BC, CD, and DA are all of equal length. For example,



However this only proves that the quadrilateral is a rhombus. To prove it is a square, you could perhaps show that one of the angles is 90, then it will follow that the quadrilateral is a square.

Take the slope of two segments. For example, the slope of line AB is



and the slope of BC is



Hence, AB and BC are perpendicular, and it follows that ABCD is a square.


Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
If the points are really the vertices of a square, then
AB to AC are perpendicular, or else,
AB to AD are perpendicular
also,
CD to CA are perpendicular, or else
CD to CB are perpendicular
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Find the equations for the pairs of points:
AB
%28y+-+%28-13%29%29+%2F+%28+x+-+6%29+=+%282+-%28-13%29%29+%2F+%28-2+-+6%29+
+y+%2B+13+=+15%2A%28x+-+6%29+
+y+=+15x+-+103+
AC
.....
Once you find the perpendicular lines, you can
draw an approximate square.
remember that slopes that are perpendicular
are related as +m%5B1%5D+=+-1%2Fm%5B2%5D+
The points that form diagonals will be obvious.