Use the diagonals to tell whether a parallelogram with the given vertices is a rectangle, rhombus, or square. Give all names that apply. Q(-8,-2) T(-6,8) W(4,6) Z(2,-4)
Search up images of graph paper then try graphing these @Seratul
I am not allowed to graph them. It would be too easy that way o.O
Can you guess from this graph?
Square and rectangle?
I think you have square but look at this one and see. Im not to sure.. Im only good at graphing points XD
Then I don't think you can help me xD. I need to make sure it is a certain shape with diagonals.
Eh well i tried XD Sowwie
Here are some points regarding diagonals of each of the mentioned figures: 1. Rectangle -> Diagonals are equal and bisect each other but not perpendicularly 2. Rhombus -> Diagonals are perpendicular bisectors of each other but not equal 3. Square -> Diagonals equal and perpendicular bisectors of each other 4. Parallelogram -> Diagonals bisect each other.. no need to be equal
Any doubt with this?
I'm pretty sure the diagonals of rectangles bisect each other perpendicularly.
Anyways, I still think it would be a square and rectangle.
A rhombus is a rectangle with all sides equal or diagonals perpendicular bisecting each other
So all three?
Q(-8,-2) T(-6,8) W(4,6) Z(2,-4) What is the order of the vertices ?
I mean the figures should be QTWZ or QWTZ or anything else?
I think the basic shape is what the previous person drew above.
Lite.. it is QTWZ...
So anyways... start by calculating the slope of QW and TZ
Can you do this?
Yea. QW: 6--2/4--8 = 8/12 = 2/3 TZ: -4-8/2--6 = -12/8= -3/2 They are negative reciprocals so they are parallel.
But we know that since they are parallelograms which is given.
Naah naah!! Because the slopes are negative reciprocals they are perpendicular... for parallel the slopes must be the same
Whoops, my bad xD.
Thus, diagonals QW and TZ are perpendicular.. thus, it can either be a square of a rhombus.. now you just need to see whether diagonals are equal or not
Use the distance formula for finding the length of QW and TZ
Why can't it be a rectangle?
Oh wait, the diagonals aren't perpendicular.
Because for a rectangle the diagonals are not perpendicular to each other...
Okay, so know we use midpoint formula?
No.. we use distance formula
We want to find out the length of QW and TZ
QW: (4--8)^2 + (6--2)^2 = 12^2 + 8^2 = 144 +64 = sqrt 208 = 4 radical 13
TZ: (2--6)^2 + (-4-8)^2 = 8^2 + -12^2 = 64 + 144 + sqrt 208 = 4 radical 13
Okay, they are the same length.
Great!
So the figure is a square
Okay, i'm going to have to memorize the properties of the parallelograms. Thank you very much!
:) Your welcome
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