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MENSURATION

P1 P2 20 MARKS

FORMULAS UNIT^ SIMILARITY CONVERSIONS (^2) D AREA (^) PERIMETER

DINOT MEMORIZE

ANY

Memorize

the

FORMULA FORPERIMETER

formula

Def SUM^

OF ALL OUTER SIDES

(^5 ) 4 4 8 Perimeter (^5 5 4 4 ) 26

1 SQUARE^ Area LXL^ L Perimeter (^) Do (^) not memorize

this

L formulaThis^ is^ just L for practice P (^) LtL LtL (^) 4L 2 w Area Law P 21 2w 2 Ltw (^3) AREA (^) OF TRIANGLE Area f

base

height paper bases

h

h h^

Édstance from THIRD point on (^) base line base A (^) find area of AABC v A gxbxh 450 5 50

a

ha b^

feigning Ingle IE c^ sides of IT (^) a

thatangle

A L c b (^) Sir A A t a c^ Sui B A t a (^) b (^) Sui c E find area^ oftriangle pin

A

L (^12 15) Sui 30

45 Q 121, Mid area of triangle 730

A

21 (^12 15) Sui (^42)

(^4) RHOMBUS PARALLELOGRAM L L h h base base

Area Base

f h 90 distance^ between

parallellines

I (^) find area of parallelogram 5

Area bth

36 (^5) TRAPEZIUM a

b

h c h a 7

b

Major

Segments Pacman (^) PIE CHORD MinorSegment SECTORS (^) SEGMENTS T (^) r r

Pacman

High

to

is feign

L T

SECTORS

Pacmanand Pizza slice^ are (^) good friends They^ use the exact (^) same formulas Are

Q

i Find area

of

sector

gift s

are 161.

ii find^ arc^ length Arclength foxar 3,

Find Perimeter

of Sector D (^8 8 41 ) 578879 SEGMENTS Area of (^) majorsegment major PACMAN

segment

TRIANGLE Area ofmajorSegment^

PACMAN TRIANGLE

T sin NOTE (^) IN MAJOR SEGMENT PACMAN AND (^) TRIANGLE

BOTH USE TWO DIFFERENT ANGLES

Find area of shaded region MINOR PIZZA (^) TRIANGLE SEGMENT Exr (^) I sin 8 (^760) EXIST ff sin6o 8

1

3 D SHAPES

VOLUME EXTERNALSURFACEAREA

Never

memorizeformula

Memorize Def Sum of areas of all

Formula

outer faces

of a (^) shape Curved (^) surface area of a (^) cone curvedsurface area of a Fcontainers cylinder To (^) surface is^ missing Circle (^) art

1 CUBE V LXLXL^ L TSA 6 12 612 L z CUBOID A wxh T A L.IE thy Lxwxh 1h

TSA 2 Lw^ 211h^ 21Wh

Top surface is^ missing

Q.Ano pencuboidcontainerisshown.find total external surface area A (^5 2 )

TotalSA^50 2 20

A L 0 2 50 40 20 (^10 2 ) 5

Q find curved^ surface area of this cake (^) slice 8 fighter^ High

h

2hr h (^10 ) 2 1871

Since cake (^) is a cylinder we use^ same^ formulas for curved (^) SA of cake slice^ too

2

Find the^ curved surface

25 say area^ of cinfiiner in FLAT (^) contact with water

CurvedSA Are

curted

surface ofcylinder^ length

FLAT in^ Coffeywith f x2ñv xh 9

are Find volume^ of this (^) cake slice

Base Volume^ Basearea^ h

94TH n

or h

h 10

0

V

V 223.

Yop

POINTED (^) SHAPES 85thIcan be any shape I BaseArea he

CONE n 1 Pythagoras slantheight L^ h m slantlength h (^2) VOLUME i

V xñr xh

3 TOTAL SURFACE

AREA

BASE CIRCLE^ ñr

Curved

Surface area^

of cone (^) Arl WHAT HAPPENS^ WHEN A^ CONE^ IS OPENED

It becomes^ a SECTOR

can be ps or Pacman

T

k

1 SLANTHEIGHT^ OF^ CONE^ BECOMES RADIUS OF SECTOR 2 CIRCUMFERENCE^ OFCONEBASE BECOMES ARCLENGTH (^) OF SECTOR 3 CURVED^ SA^ OF^ CONE^ BECOMES

AREA OF^ SECTOR

SIMILARITY

1 AAA

If all^ angles of two (^) differentsizedshapes are

equal they

are similar

2 FOR SIMILAR SHAPES RATIO OF CORRESPONDING LENGTHS

IS EQUAL

r E (^) EE L r e H R J Q check^ if both (^) shapes are^ similar 20 (^7) g 2

A

6 B

E I (^) I

no these shapes

are not^ similar I (^) I I X

IF TWO SHAPES^ ARE SIMILAR

WE DO^ NOT^

APPLY

MENSURATION FORMULAS

TO FIND AREA VOLUME

corresponding AREA 41 E ratio of sides

volume

Y (^) I

mass

It fi Q

Conca and ConeB are Similar

B

A

g 15 x (^9) F (^) F

K