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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

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?
ninjadapaul
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
ninjadapaul
I don't understand what the A with approx sign and the boxed x mean
ninjadapaul
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
ninjadapaul
oops. ignore that.
ninjadapaul
so you not have an equal sign anywhere in the original equation?
ninjadapaul
Commplementary angles
Idrissa Reply
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
hii
Uday
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
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Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
Kim
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Al
y=10×
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
is it 3×y ?
Joan Reply
J, combine like terms 7x-4y
Bridget 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
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
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Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
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
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
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
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
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
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
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 8. OpenStax CNX. Sep 11, 2009 Download for free at http://cnx.org/content/col11033/1.1
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