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4. Los die vergelyking op.

5. Beantwoord dan die vraag.

Kom ons kyk na ’n paar voorbeelde:

Voorbeeld 1:

Probleem : Die lengte van ’n reghoek is 5 cm meer as sy breedte.


1) Teken ’n reghoek

2) Vra jouself: “Van watter een, lengte of breedte, weet jy niks?”in die geval: breedte = x cm

3) Druk nou die lengte uit in terme van x : in die geval: ( x + 5)(onthou 5 meer : d.w.s. x + 5)

4) Nou kan die vraag ook sê as die omtrek 80 cm is, bereken die lengte en breedte van die reghoek.(Nou kan jy die gegewens as ’n vergelyking voorstel)

Doen dit nou:

5) Los nou die vergelyking op en beantwoord die vraag in (4).

Voorbeeld 2:

Probleem : ’n Ma is vier keer so oud soos haar dogter. Hulle gesamentlike ouderdomme is 60. Hoe oud is hulle elk?


1) Vra jouself: “Van watter een weet jy niks? ” en laat dit x wees.

2) Maak ’n voorstelling van jou denke tot dusver:

Ma Dogter

4 x x

3) Stel die gegewens nou as ’n vergelyking voor, los die vergelyking op en beantwoord die vraag.

Voorbeeld 3:

Die probleem met ouderdomme is altyd ’n toffie, maar doen dit stap vir stap, skryf die plan neer van hoe jy dink en dit is baie maklik.....

Probleem: Milandre is 30 jaar ouer as Filandre. Oor 15 jaar sal Milandre twee keer so oud soos Filandre wees. Hoe oud is elk nou?


1) Begin met ’n plan en skryf dit neer:

2) Vra jouself: “Van watter een weet ek niks?” en maak dit x .

ouderdom: nou

ouderdom: oor 15 jaar

(d.w.s + 15)

Milandre x + 30; ( x + 30) + 15

Filandre x; x + 15

3) Nou kom die moeilikste deel: oor 15 jaar sal Milandre twee keer so oud soos Filandre wees. Milandre is reeds dan twee keer so oud soos Filandre en jy sal Filandre se ouderdom (in die kolom oor 15 jaar) met 2 moet vermenigvuldig sodat jy ’n vergelyking kan kry (d.w.s linkerkant = regterkant)

4) Skryf jy nou die vergelyking hier neer, los dit op en beantwoord die vraag.

Kyk op jy nou die volgende op jou eie kan doen. Onthou jy moet ’n “plan” soos jy dink telkens neerskryf.

Hier kom hulle .....

1. Die som van twee getalle is 15. Skryf die twee getalle in terme van x , neer.

2. 140 mense woon die Steve Hofmeyer konsert by.

Die volgende kaartjies is beskikbaar:

Kinders: R 20

Volwassenes: R 45

As die toegangsgeld R 5 580 beloop het, bereken hoeveel volwassenes en hoeveel kinders teenwoordig was.


1. Gegee: a ∈ {-4; -3; -2; -1; 1; 2; 3}Kies elke keer jou antwoord uit bogenoemde versameling.

1.1 -3 a + 20 = 23

1.2 8 a = -32

2. Die waarde van x word in elke geval gegee. Toets die korrektheid van elke vergelyking.

2.1 8 x - 2( x - 5) = 28 x = 3

2.2 5 x - 10 = 10 x - 10; x R

3. Los elk van die volgende vergelykings op. Wys al jou berekeninge.

3.1 1 / z = 1 / 18 ; z = ?

3.2 1 - 5 z = 11

3.2.1 waar z N

3.2.2 waar z ∈ Q

3.3 z + 3[ z + 2( z - 6)] = 45

3.4 4(6 z - 8) - 2( z + 7) = 37

3.5 z - 5( z - 8) = -48

4. Skryf elk van die volgende as algebraïese vergelykings en los dit dan op.

4.1 Ses keer ’n getal, verminder met 8 is gelyk aan 55. Bereken die getal.

4.2 ’n Negatiewe getal is nege keer die ander getal. Die som van die twee getalle is -64. Bepaal die twee getalle.

4.3 Die som van drie opeenvolgende negatiewe heelgetalle is -90.Bepaal die drie negatiewe getalle.

Questions & Answers

how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket 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
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 8. OpenStax CNX. Sep 11, 2009 Download for free at http://cnx.org/content/col11033/1.1
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