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April 25th, 2019, 01:06 PM   #1
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Show these point form a square

Show ACDE is a square

C=10,2

A=4,2

E=8,-8

D=14,-4

Last edited by skipjack; April 25th, 2019 at 08:38 PM.
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April 25th, 2019, 01:17 PM   #2
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They don't. Side lengths are different.
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April 25th, 2019, 03:49 PM   #3
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Should be $A = (4,-2)$. Also, what have you tried?
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April 25th, 2019, 04:01 PM   #4
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Quote:
Originally Posted by SDK View Post
Should be $A = (4,-2)$. Also, what have you tried?
Yes you're correct. I know it's a square. I have found all side lengths to be approximately 7.21 units or √52 and the diagonal from AD and CE are √104 or approximately 10.19 units and they are all at right angles to each other. What are some mathematical statements I can use?

Last edited by skipjack; April 25th, 2019 at 08:35 PM.
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April 25th, 2019, 11:18 PM   #5
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The easiest approach is to show that the diagonals are mutually perpendicular and have a common mid-point. This suffices to establish that ACDE is a square and doesn't require use of Pythagoras.
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April 26th, 2019, 01:36 PM   #6
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If all angles are right angles and side lengths the same, it is a square.
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April 26th, 2019, 01:45 PM   #7
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This makes me cry. Use vectors!
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