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Graad 9


Module 21



Om sommige vierhoeke te verken en hul kenmerke te identifiseer

[LU 3.4]

Hier kry jy met sommige baie belangrike vierhoeke te doen. Ons moet hul kenmerke ken, want hulle kom oral om ons voor in die natuur, maar veral in mensgemaakte voorwerpe.

Aangesien jy lynlengtes en hoekgroottes sal moet meet, moet jy seker maak dat jou liniaal en gradeboog byderhand is. Bring ook ‘n skêr saam vir die uitknip van vierhoeke.

Ons begin egter eers met die woord vierhoek. Dit beskryf ‘n plat figuur met vier reguit sye en dus vier hoeke. Ons gaan die sye bestudeer (dikwels in teenoorstaande pare); die binnehoeke (ook dikwels in pare); die diagonale (of hoeklyne), en simmetrie–lyne.

Let op vir nuwe terme en maak seker dat jy hulle goed begryp voordat jy voortgaan.

1. Simmetrie-lyne

Jy is alreeds goed bekend met die vierhoek wat ons ‘n vierkant noem.

Die vierkant

Op die werkvel met vierhoeke is ‘n figuur: “VIERKANT”. Knip dit netjies uit en vou dit om vas te stel of dit enige simmetrie–lyne het.

Simmetrie-lyne is dié lyne waarlangs ‘n mens enige figuur kan vou sodat die twee dele presies opmekaar val.

Maak doodseker dat jy al die simmetrie-lyne gekry het. Teken dan die lyne in op die skets langsaan, met ‘n liniaal. Daar is alreeds een van hulle ingevul as ‘n voorbeeld.

Toevallig is die stippellyn op die skets ook ‘n hoeklyn (diagonaal), aangesien dit van die een hoek na die ander een skuins oorkant getrek is.

- Kyk ‘n bietjie om jou. Kan jy vinnig ‘n vierkant raaksien?

As die vierkant skuins gedruk word, sonder om van grootte te verander, word dit ‘n ruit.

Die ruit

Identifiseer die RUIT op die werkvel. Dit behoort duidelik soos ‘n vierkant wat skuins staan, te lyk. Knip dit uit sodat jy dit kan vou om die simmetrie–lyne op te spoor. Die ruit word ook ‘n rombus genoem.

Weer eens, trek die simmetrie-lyne in op die skets hier langsaan.

- Is die stippellyn in hierdie skets ‘n simmetrie-lyn?

As ons nou die ruit uitrek, word ‘n parallelogram gevorm.

Die parallelogram

Soek die PARALLELOGRAM op die werkvel.

Knip dit uit; vou dit en soek weer die simmetrie-lyne; trek die lyne in op die skets.

- Om iets met ‘n parallelogram-vorm te kry, sal jy lank moet soek. Huiswerk: Kyk of jy iets binne 24 uur kan kry!

Hierdie parallelogram word ‘n reghoek as ons dit regop druk.

Die reghoek

Knip die REGHOEK uit om die simmetrie-lyne te kry om op die sketse in te vul.

- Skryf al die verskille neer wat jy opmerk tussen ‘n reghoek en ‘n vierkant.

As ons nou die twee sykante van die reghoek in verskillende rigtings draai, kry ons ‘n trapesium.

Die trapesium

Die werksvel bevat meer as een TRAPESIUM. (Hier is nog ‘n trapesium langsaan.) Knip hulle uit om die simmetrie-lyne te vind.

- Beskou nou al die soorte trapesiums en skryf ‘n paar sinne om te verduidelik hoe jy hulle sou herken.

Daar is twee soorte VLIEËRS op die werkvel. Knip hulle uit en soek simmetrie-lyne.

Julle weet sekerlik almal wat ‘n vlieër is – die speelding wat aan ‘n toutjie in die lug rondvlieg. Moderne vlieërs het allerhande oulike vorms, maar die vierhoek is vernoem na die eenvoudige papiervlieërs wat maklik gemaak kan word uit twee dun stokkies van verskillende lengtes, papier, gom, ‘n tou, en ‘n stert om dit te stabiliseer.

Questions & Answers

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
how do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
is it a question of log
Commplementary angles
Idrissa Reply
im all ears I need to learn
right! what he said ⤴⤴⤴
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Wiskunde graad 9. OpenStax CNX. Sep 14, 2009 Download for free at http://cnx.org/content/col11055/1.1
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