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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.

Oplossing:

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?

Oplossing:

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?

Oplossing:

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.

HUISWERKOPDRAG 1 en 2

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

what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
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
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
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.
Tarell
what is the actual application of fullerenes nowadays?
Damian
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.
Tarell
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.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
Got questions? Join the online conversation and get instant answers!
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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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