Question

2. A parallelogram has the vertices (-1, 2), (4, 4), (2, -1) and (-3, -3). Determine what type of parallelogram [10 points]. Find the perimeter and area [20 points].

Answer 1

That's what I got...but clearly it's not a parallelogram, so what am I doing wrong, and what do I need to do differently?

Answer 2

@ganeshie8, please help!

Answer 3

http://prntscr.com/3eu6hv

Answer 4

^^thats how it should look.
graphing is a very good idea, but u dont need to graph to solve this problem.

Answer 5

Ohhh...duh.
Apparently I'm going to be stupid today, brilliant. Thnx for the help! :)

Answer 6

u figured how to work the problem ?

Answer 7

BTW, someone told me the answer to this problem was 12. Are they right? I got 4.2...
√((3) – (0))² + ((0) – (3))² = √3² + -3² = √9 + 9 = √18 ≈ 4.2

Answer 8

yes, I did

Answer 9

show me ur complete work

Answer 10

For the first problem?

Answer 11

for both

Answer 12

Ah...ok

Answer 13

what ever u have so far...

Answer 14

just a mo, then

Answer 15

working on the second question now

Answer 16

Are you given instructions that u need to work it by graphing ?

Answer 17

Yeah, they taught graphing and the distance formula and whatnot

Answer 18

no, i mean did the instructions specifically ask u to do this by graphing ?

Answer 19

cuz, u should NOT use graphing unless the instructions say so

Answer 20

the common/regular way to work this problem is by finding lengths of sides using `distance formula` and the slopes of sides using `slope formula`

Answer 21

http://static.k12.com/eli/bb/343/-1/0/1_124724_23955/-1/0c7f4350276a46b214395670eae2d3ec752620d8/media/e3eb7b41ab24f0e612428cb2ca67db83e139e1b7/83879.PDF

Answer 22

Those were the directions they gave me

Answer 23

cool :) then you're right ! they want u work it by graphing

Answer 24

Given that they gave me the graph, I would assume that they want me to solve it by graphing, but I also used the distance formula to find the lengths of the sides

Answer 25

ok :)

Answer 26

good :)
your length of sides, and perimeter are correct.
but Area is wrong.

Answer 27

squaring sides will not give u Area for a rhombus.

Answer 28

ohh..just looked it up A - diagonal x diagonal/2

Answer 29

Area of rhombus = \(\frac{1}{2} d_1 d_2\)

Answer 30

yes^

Answer 31

Great, now I have to find the diagonals, lol

Answer 32

its easy from graph

Answer 33

horizontal diagonal = 3--3 = 6
vertical diagonal = 3--3 = 6

Answer 34

So, Area = \(\frac{1}{2} d_1 d_2 = \frac{1}{2} 6*6 = 18\)

Answer 35

And that makes the given rhombus a SQUARE !

Answer 36

so the given parallelogram is not just a rhombus, its also a SQUARE !

Answer 37

for the `type of parallelogram `, you should say that its a `square`

Answer 38

if that makes any sense..

Answer 39

The parallelogram is a rhombus and a square?

Answer 40

just say its a SQUARE !

Answer 41

rhomus: all equal sides, two pairs of equal angles
square: equal sides, equal angles

Answer 42

oh, ok

Answer 43

Does that change my equation for the area, then?

Answer 44

all squares are parallelograms
all squares are rhombuses
all squares are rectangles
all squares are quadrilaterals

Answer 45

a square is many things

Answer 46

yes it will change ur formula, but the answer will be same

Answer 47

I see that, lol

Answer 48

let me modify it and give u

Answer 49

it will be?

Answer 50

ok

Answer 51

here is the corrected stuff for question 1 :
http://prntscr.com/3euc4h

Answer 52

how do you find the diagonals inside a rhombus?

Answer 53

use the distance formula

Answer 54

oh, its the same process, ok, hold on

Answer 55

ok, i presume u knw what a diagonal is :)

Answer 56

it just connects the opposite vertices

Answer 57

^^those two line segments joining opposite vertices are diagonals

Answer 58

Is that correct? I found it odd that I got the same area for #1 and #2...but maybe that's just a coincidence

Answer 59

diagonals are not equal in rhombus

Answer 60

so u need to calculate the 2nd diagonal also using distance formula

Answer 61

and then use the area of rhombus formula :

Area = \(\frac{1}{2}d_1 d_2\)

Answer 62

@ganeshie8

Answer 63

looks good !

Answer 64

thnx! :D