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PREPARATORY EXAMINATIONVOORBEREIDENDE EKSAMEN
2019MARKING GUIDELINES /
NASIENRIGLYNE
MATHEMATICS (PAPER 2) (10612)WISKUNDE (VRAESTEL 2) (10612)
22 pages / bladsye
10612 / 19
GAUTENG DEPARTMENT OF EDUCATION /
GAUTENGSE DEPARTEMENT VAN ONDERWYS
PREPARATORY EXAMINATION /
VOORBEREIDENDE EKSAMEN
MATHEMATICS / WISKUNDE(Paper 2 / Vraestel 2)
MARKING GUIDELINES / NASIENRIGLYNE
NOTE: If a candidate answers a question TWICE, only mark the FIRST attempt. If a candidate has crossed out an attempt of a question and has not redone the question, mark the
crossed out version. Consistent accuracy applies in ALL aspects of the marking guidelines. Stop marking at the
second calculation error. Assuming answers / values in order to solve a problem in NOT acceptable.
LET WEL: As ʼn kandidaat ʼn vraag TWEE KEER beantwoord, sien slegs die EERSTE poging na. As ʼn kandidaat ʼn antwoord van ʼn vraag doodtrek en nie oordoen nie, sien die doodgetrekte
poging na. Volgehoue akkuraatheid word in ALLE aspekte van die nasienriglyne toegepas. Hou op nasien by
die tweede berekeningsfout. Aannames van antwoorde / waardes om ʼn probleem op te los, word NIE toegelaat nie.
GEOMETRY / MEETKUNDE
S
A mark for a correct statement(A statement mark is independent of a reason.)ʼn Punt vir ʼn korrekte bewering(ʼn Punt vir ʼn bewering is onafhanklik van die rede.)
R
A mark for a correct reason (A reason mark may only be awarded if the statement is correct.)ʼn Punt vir ʼn korrekte rede(ʼn Punt word slegs vir die rede toegeken as die bewering korrek is.)
S / R Award a mark if the statement AND reason are both correct.(Ken ʼn punt toe as beide die bewering EN rede korrek is.)
2
10612 / 19
QUESTION / VRAAG 1
Number of oranges in the bag Aantal lemoene in sak 18 16 20 15 14 13 14 10
Median mass of oranges in the same bag (to the nearest gram) / Mediaangewig van die lemoene in dieselfde sak (tot die naaste gram)
110 105 72 142 123 174 136 192
8 10 12 14 16 18 20 220
50
100
150
200
250
SCATTER PLOT / SPREIDINGSDIAGRAM
Number of oranges in a bag / Aantal lemoene in sak
Med
ian
mas
s of o
rang
es /
Med
iang
ewig
van
lem
oene
1.1 a = 307 , 20b = −11 ,70y = 307 ,20 − 11 ,7 x
a = 307 , 20b = −11 ,70 y = 307 ,20 − 11 ,7 x
(3)1.2 r =−0 , 93 r =−0 ,93
(1)1.3 See scatter plot above/sien spreidingsdiagram hierbo
(10 ; 190,2) (20 ; 73,2)
(10 ; 190,2) (20 ; 73,2)
(2)1.4 Negative strong association /
Negatiewe sterk assosiasieanswer / antwoord
(1)1.5 y = 307 , 20 − 11 ,7 (12)
= 166 ,8substitution / vervanganswer / antwoord
(2)[9]
3
10612 / 19
QUESTION / VRAAG 2
2.1.1 100 answer / antwoord (1)2.1.2 Median / Mediaan = ±62 answer / antwoord
(Accept / Aanvaar 61 / 62) (2)
2.1.3 Q1= 37/38Q3 = 72/73
Q2= 61/62 & min & max / min & maks (10 & 100)
(3)
2.1.4 Skewed to the left / Skeef na links left / links(1)
2.2 b = 20d − a2
= 8
2 a = d
sub 2a − a2
=8
a = 16d = 325+16+19+20+c+32+35=7×22∴ c = 27
b = 20
a = 16d = 32
c = 27 (4)[11]
4
10612 / 19
QUESTION / VRAAG 3
3.1
3.1.1 1=3+ x
22=3+ xx=−1
−2=4+ y2
−4=4 + yy=−8
B(−1 ; −8 )
1=3+x
2
−2= 4+ y
2
B(−1 ; −8 ) (3)
3.1.2 mCD=0−46−3
¿−43
substitution into gradient formula / vervang in gradient formule
mCD=−4
3 (2)3.1.3
y−2=−43
( x−11)
y=−43
x+503
OR / OF
substitute m /vervang m substitute / vervang Q(11;2)
(2)
5
R
D(3 ; 4)
0 C(6 ; 0)
A
B
Q(11 ; 2)
P(1 ; )
y=−43
x+c
2=−43
(11 )+c
c=503
y=−43
x+503
10612 / 19
3.1.4
D is the
midpoint of PR / D is die middelpunt van PRC is the midpoint of PQ (line from midpoint of 1 side || to 2nd side)/C is die middelpunt van PQ (lyn van middelpunt van 1 sy || aan 2de sy)
RQ=2CD=10 (midpoint theorem / middelpunt stelling )
PK = RQ√ ( y + 2 )2 + ( 4 − 1 )2 = 10( y + 2 )2 + ( 4 − 1 )2 = 10 2
( y + 2 )2 = 91 or / ofy + 2 = ± √91y = ±√91 − 2y =−11 ,54or / ofy≠ 7 ,54
CD = 5 OR / OF R(5 ; 10)
statement / bewering
RQ = 10
correct substitution into distance formula / korrekte vervanging in die afstandsformule
simplification / vereenvoudiging
y =−11 ,54(6)
6
R (5 ; 10 ) midpoint / middelpuntRQ=√(2−10 )2 + (11 − 5 )2
RQ= 10
CD=√ ( y2− y1)2+(x2−x1 )2 OR / OF
¿√ (0−4 )2+(6−3 )2
¿√25CD=5
10612 / 19
3.2
3.2.1 mPQ=tan θtanθ=1θ=45 °
P¿
1=35 ° vertical opp ∠ s / regoorst ∠eQR || to the x-axis / aan die x-as
T¿
1=35 °+ 45° ext ∠ of Δ / buite ∠ v Δ
T¿
1=80°
α=T¿
1=80 ° corr∠ s ST||QR / ooreenkomstige ∠e ST||QR
OR / OF mPQ=tan θtanθ=1θ=45 °QR || to the x-axis / aan die x-as
S1
¿
=Q¿
=45 ° corr∠ ’s ST||QR / ooreenkomstige ∠ ’e ST||QR
P¿
1=35 ° vertical opp∠ s / regoorst ∠e
α=35 °+ 45°α=80 ° ext ∠ of Δ / buite ∠ v Δ
mPQ= tan θ
θ=45 °
P¿
1=35 °
T¿
1=80°
α=T¿
1=80 °
OR / OF
mPQ= tan θ
θ=45 °
S1
¿
=Q¿
=45 °
P¿
1=35 °
α=T¿
1=80 °
7
P
T
S
0
U
1 1
1
θ
10612 / 19
(5)3.2.2
x at/by U:
U2+(−8 )2
=1
∴U x=10 units / eenhedeQU =18 units / eenhede
x at/by W = x at / by U = 10
y at/by W:
y=10+23
=323
WU =
323
+5 =473
∴Area ΔQWU=12
(18 )(473 )
=141 square units /eenhede kwadraat
U x=10units / eenhedeQU = 18 units / eenhede
U = 10
WU =
473
correct substitution in area formula / korrekte vervanging in oppv. formule
141 square units /eenhede kwadraat
(6)[24]
8
10612 / 19
QUESTION / VRAAG 4
4.1 T U¿
S=180°−101, 31 °=78 ,69 ° adj supp∠ s / aangrensende suppl ∠e mTU=tan78 , 69 °=5c=6y=5 x+6
T U¿
S=78 ,69 °
mTU=5
y=5 x+6(3)
4.2 x−int /afsnit y=0−15
x + 45
= 0
−x+4=0x=4∴S( 4 ; 0 )
M=(−6+42
; 2+02 )
∴M (−1 ; 1)
OR / OF
S( 4 ; 0 )substitute correctly / korrekte vervangingM (−1 ; 1 )
9
OQ
y
L
M
Kx
U S
101,31°
10612 / 19
At M:
5 x+6=−13
x+45
265
x=−265
x=−1y=−1∴M (−1; 1)
CANDIDATE MUST SHOW CALCULATIONS TO GET MARKS IN THIS QUESTION / KANDIDAAT MOET BEREKENINGS TOON OM PUNTE IN HIERDIE VRAAG TE VERDIEN
5 x+6=−
13
x+45
x = –1
y = 1
(3)
4.3 ( x+1 )2+( y−1 )2=r 2
(−6+1 )2+(2−1 )2=r2
r2=26( x+1 )2+( y−1 )2=26
OR / OF( x+1 )2+( y−1 )2=r 2
(4+1 )2+ (0−1 )2=r2
r2=26( x+1 )2+( y−1 )2=26
substitute / vervang (−6 ; 2 )
r2=26
( x+1 )2+( y−1 )2=26OR / OF
substitute / vervang(4 ; 0 )
r2=26
( x+1 )2+( y−1 )2=26
(3) 4.4 mMP=−1
5 mMP×mKL=−1
mKL=5 radius⊥ tan /radius⊥raaklyn
mTU=5 proven / reeds bewys∴mTU=mKL=5KL||TU
mMP=−1
5
mKL=5
mTU=5
(3)4.5
VM = √(−1 + 12 )
2+ (1 − 7 )2
¿ 6,02
radius = √26 = 5,16,02 > 5,1
∴V (−12
; 7)does not lie within the circle . /l e nie binne die sirkel nie .
VM = 6,02
6,02 > 5,1
conclusion / gevolgtrekking
10
10612 / 19
(3)[15]
QUESTION / VRAAG 5
5.1.1 x2=(√1+k2)2−(1 )2 (Pythagoras )x2=k2
x=k
tan16°=1k
x=k
tan16 °= 1
k(2)
5.1.2 cos32 º=cos2 (16 ° )=2cos2 16 º−1
¿2(k√1+k2 )
2−1
OR / OF
cos32 º=cos2 (16 ° )=cos216 º− sin216º
¿(k√1+k2 )
2− (1
√1+k2 )2
OR / OF
cos32 º=cos2 (16 ° )=1 − 2sin216 º
¿1 − 2 (1√1+k2 )
2
cos2 (16 ° )2 cos216 º−1
correct substitution / korrekte vervanging
OR / OF
cos2 (16 ° )
cos2 16 º− sin2 16 º
correct substitution / korrekte vervanging
OR / OF
cos2 (16 ° )
1 − 2sin216 º
correct substitution / korrekte vervanging (3)
11
111
60º
10612 / 19
5.2 cos (90 ° + x ) sin ( x−180 º ) − cos2 (180 ° − x )cos (−2x )
¿(−sin x )(−sin x ) − cos2 xcos 2x
¿sin2 x − cos2 xcos2 x − sin2 x
OR / OF −cos 2 xcos 2 x
¿−( cos2 x − sin2 x )cos2 x − sin2 x
=−1
¿ −1
−sin x–sin x
–cos2 x
cos 2 x
–(cos2 x − sin2 x ) OR / OF–cos 2 x –1
(6)5.3 cos75 ° .cos 45 ° − cos15 ° . cos 45°
=cos75° . cos45 °−sin75 ° .sin 45 °=cos (75 ° + 45 ° )=cos120°=−cos60 °
=−12
OR / OF
cos75 ° .cos 45 ° − cos15 ° . cos 45°=sin15 ° .cos 45 °−cos 15° . sin 45 °=sin (15 ° − 45 °)=sin (−30° )=−sin 30°
=−12
cos75 ° .cos 45 °−sin 75 ° . sin 45 °
cos (75° + 45 °)
−cos60 °
− 1
2
OR / OF
sin 15 ° . cos 45°−cos15 ° . sin 45 °
sin (15 ° − 45 ° )
−sin 30 °
− 1
2(4)
5.4.1tanθ (sin 2θ + 3 cos2 θ
sin θ )¿ sin θ
cosθ (2 sin θ cosθ+3 cos2θsin θ )
¿2 sin2 θ+3 cosθ¿2 (1−cos2θ )+3 cosθ=−2 cos2θ + 3 cosθ + 2
2 sin θ cosθ and / en
sin θcosθ
simplification / vereenvoudiging
1−cos2 θ
(3)5.4.2 −2 cos2 θ + 3 cosθ + 2=0
2 cos2 θ−3cosθ−2=0(2 cosθ+1 ) (cosθ−2 )=0
factors / faktore (2 cosθ+1 ) (cosθ−2 )
both equations / beide
12
10612 / 19
cosθ=−12
or / of cos θ=2
no solution / geen oplossingref / verwy ∠ = 60 °
θ=±120 °+k 360° ; k∈Ζ OR / OF θ = 120 ° + k360 ° ;k∈Ζθ = 240 ° + k360 ° ; k∈Ζ
vergelykings
cosθ=−12
or / of cosθ=2
no solution / geen oplossing
θ=±120∘+k 360∘ k∈Ζ OR / OF
θ = 120 ° + k 360 °; k∈Ζθ = 240 ° + k 360 ° ; k∈Ζ
(4)5.5
cos (a + b) = −√22
ref ∠/ verw ∠= 45°
a + b = 180 ° − 45 °a + b = 135 ° .. .. . .. .. .. . (1)
cos ( a− 2b ) = 12
ref ∠ /verw ∠= 60 °
a − 2b = 60° .. .. . .. .. . .. .. . . (2)
3b = 75 ° (1)−(2)b = 25 °a = 110°
a + b = 135 °
a − 2b = 60 °
b = 25 °a = 110°
(4)[26]
13
10612 / 19
QUESTION / VRAAG 6
6.1
(45° ; −1
2 ) x-intercepts / x-afsnitte
shape / vorm
asymptotes / asimptote
(4)
6.2 y∈ [ 2 ;4 ] OR / OF 2≤ y≤4 y∈ [ 2 ;4 ] OR / OF 2≤ y≤4
(1)6.3 x∈ [ 135° ; 180 ° ] OR / OF 135 °≤x≤180°
x∈[ 225 ° ; 270 ° ) OR / OF 225 °≤x<270°
x∈ [ 135° ; 180 ° ] OR / OF 135 °≤x≤180 °x∈[ 225 °;270 ° ) OR / OF 225 °≤x<270 °
(2)[7]
14
0
1
2
-1
-2
225 ° 270 °
10612 / 19
QUESTION / VRAAG 7
7.1 D1=180°−60 °−(120 °−α ) (sum of ∠ s of Δ / som vd ∠e v Δ )D1=α
D1=180 °−60°−(120 °−α )
D1=α(2)
7.2 BDsin60 °
=4sinα
BD sinα=4 sin60 °
BD=4 (√3
2 )sinα
BD=2√3sinα
substitution into correct sin rule / vervang in korrekte sin reël
simplification / vereenvoudiging
answer / antwoord(3)
7.3
In Δ ADB:A { D B=θ (∠s of a Δ ) ¿ ABBD
=tan θ ¿AB=BD. tan θ ¿ =2√3sinα
. tan θ ¿AB=2√3 tan θsin α
¿¿A D B=θ
trig ratio / trig verhouding
substitution of BD / vervanging van BD
(3)[8]
15
D B1
C
A
4
10612 / 19
QUESTION / VRAAG 8
8.1 O2 = 50 °D1 = 25 °
∠ saround a point / ∠ e om ʼn punt∠centre = 2¿∠ at circumferencemidpts ∠ = 2 ¿ omtreks ∠
S
SR
(3)8.2 B3 = 25 ° tan chord theorem /
raaklyn koordstellingSR
(2)
8.3 BC D=120 ºB2=35ºO B C=O C B=65 º∴ B1=65 º−35 ºB1=30º
OR / OFBC D=120ºB2=35ºB1 + B2+ B3 = 90 °B1 = 30 °
opp∠ sof a cyclic quad /teenoorst ∠ e v kvh
sum of ∠ sof a triangle / som ∠ e v Δ∠ sopp. equal radii / ∠ e teenoor gelyke radiuse
OR / OF
opp∠ sof a cyclic quad/teenoorst ∠ e vkvh
sum of ∠ sof a triangle / som ∠ e v Δradius¿ tangent / radius ¿ raaklyn
S / R
SS
answer / antwoord
S / RS
Sanswer /
antwoord(4)
[9]
16
D1
221
CP
310º
3
2 1
2 1
O
BA
T
10612 / 19
QUESTION / VRAAG 9
9.1 Equal / gelyk. answer / antwoord (1)
9.2
9.2.1 D1 = F1=xF1 = F2=x
tan chord theorem / raaklyn koordstelling
= chords subtend = ∠ s = koorde onderspan = ∠ e
S / R
SR
(3)9.2.2 F2 = A=x
D1 = A=xABDC is a cyclic quad / ABDC is ʼn kvh
ext.∠of cyclic quad / buite ∠ v kvh
ext ∠= opp int ∠ OR converse of ext.∠of cyclic quad / buite ∠ = oorst binne ∠OF omgekeerde buite ∠ v kvh
SR
R
(3)9.2.3 B1 + B2 = A
A = D1
B1 + B2 = D1
BE||CD
tan chord theorem / raaklyn koordstelling
proved / reeds bewys
correspond ∠ s = / ooreenkomst ∠ e =
S
R(2)
17
A
E C
112
21
F
2 x
D1B
P
10612 / 19
9.2.4 C1 + C2 + F1 + F2 = 180 °
C1 = C2
F1 = F2
2 C1+ 2 F2 = 180 °C1 + F2 =90°E1 = 90°
FC is a diameter of circle FDCE.FC is ʼn middellyn van sirkel FDCE.
OR / OF
Let F1 = F2 = xC = 180 ° − 2x
C1 = C2 = 90° − x
In ΔFDC or / of ΔEFCD = 90 ° or / of E = 90 °
FC is a diameter of circle FDCE.FC is ʼn middellyn van sirkel FDCE.
opp∠ sof a cyclic quad / teenoorst ∠ e v kvh
diag rhombus bisect ∠ / diag ruit halveer ∠
proved / reeds bewys
sum of ∠ s of Δ / som van ∠ e v Δ
converse∠ in a semi circle /
omgekeerde∠ in half sirkel
proved / reeds bewys
opp∠ sof a cyclic quad / teenoorst ∠ e v kvhdiag rhombus bisect ∠ / diag ruit halveer ∠
sum of ∠ s of Δ / som van ∠ e v Δ
converse∠ in a semi circle /
omgekeerde∠ in half sirkel
SR
S
S
R
OR / OF
SR
S
S
R (5)
[14]
18
10612 / 19
QUESTION / VRAAG 10
10.1
NB: NO construction 0 / 5 / GEEN konstruksie 0 / 5
On sides KL and KM of Δ KLM mark points A and B respectively such that KA = GH and KB = GI. Draw AB
Op sye KL en KM van plaas A en B onderskeidelik sodat
KA = GH en KB = GI. Trek lyn AB.
Proof / Bewys
In ΔGHI and/ en ΔKABKA = GH construction / konstruksieK = G given / gegeeKB = GI construction / konstruksie∴ ΔGHI ≡ ΔKAB S∠S∴ A1 = Hbut { L
= H given / gegee ¿ ∴ A1=L ¿∴AB || LM corr .∠s =¿ooreenkomst . ∠e = ¿KLKA
= KMKB
line || one side Δ/ lyn || een sy v Δ ¿∴KLGH
= KMGI
¿¿
construction / konstruksie
S / R ΔGHI ≡ ΔKAB S∠ SS
R
S / R
(5)
19
K
L M
G
H I
o o
..
A B1
Δ KLM
10612 / 19
10.2
10.2.1 R1=60 º equilateral Δ / gelyksydige ΔW 1=P1+Q1 ext .∠of a Δ / buite ∠ v Δ¿60º + Q1
¿ R1+Q1
Q1=R2 ∠ s in the same segment/∠e in dieselfde segment
∴W 1=T R Q
S
S
S / R
(3)
10.2.2 In ΔTQR and / en ΔQRV1 . W 1=T R Q proved / reeds bewys2 . R1 = T Q R equilateral Δ/ gelyksydige Δ3 . Q2=T sum ∠s of Δ / som van ∠e v Δ ∴ΔWRQ ||| ΔRQT ∠∠∠
SS
R (3)
20
T
P
V
W
1
12
2
21
R
Q
1
1
10612 / 19
10.2.3
In ΔTPV and / en ΔWQR1 . P Q R= R1 both 60º / albei 60 ° P { Q
R=V 1 ext . ∠ of a cyclic quad . / buite ∠ v kvh ¿ V 1 = R1 ¿2 . P2=T R Q ext . ∠ of a cyclic quad . / buite ∠ v kvh ¿ but / maar W1=T R Q proved / reeds bewys ¿ { P ¿2=W1 ¿3 . T=Q2 sum of ∠s of Δ / som v ∠e v Δ ¿ΔVPT ||| ΔRWQ ∠∠∠ ¿VPRW
=PTWQ
=VTRQ
corresponding sides in prop/ ¿ ooreenkomstige sye in verhouding ¿∴PTWQ
=PVWR
¿¿
S
S / R
S
S
S R
(6)[17]
21
10612 / 19
QUESTION / VRAAG 11
11.1 PEEQ
= PDDO
x9
=
23
x
x + 3x2 + 3x = 6 xx2 − 3 x =0x ( x − 3 )= 0x = 0 or/ of x = 3N . A / n .v . tDO = 6DO = OROR = 6 units / eenhede
line || one side ΔPOQ OR prop theorem ED||OQ / lyn || een sy ΔPOQ OF eweredigheid stelling ED||OQ
radii / radiusse
SR
x = 3
OR = 6 (4)11.2 S is the midpoint of RE / S is die
middelpunt van REDE =2OSDE = 2,8 units / eenhede
midpoint theorem / middelpunt stelling
Ranswer (2)
11.3 Area ΔPEDArea ΔPER
= PDPR
= 214
= 17
same height (DE) / dieselfde hoogte (DE)
SR
17
Area ΔPER = 7 ¿ Area ΔPED = 18,9 units2 / eenhede2 18,9 (4)
[10]
TOTAL / TOTAAL [150]
22
P
D
+ 3E
O
S
QR
x +9