Krishna Pai − Profile

yes take max length as 3km and solve 

you  will get 15cm as length of scale

did you take max lenght as 3km?

3 KM

take EDC=90

ADC=90{linear pair}

ABC=90{cyclic quadlilateral,opp angles add up to 180}

EGA =50 GIVEN

BY EXTERIOR ANGLE THEOREM

ABC=BCG+CGB

90=BCG+50

BCG=40

BAC=40{ALERNATE SEGMENT THEOREM}

ACB=180-90-40

ACB=50

area(bef):area(abd)=4:9

2:3

SP=12cm

K=13

K=13

let SPT=x,

QRT=y

SRQ=180-x{cyclic quad}

SRQ+QRT=180{linear pair}

180-x+y=180

y=x

SPT=QRT

T common angle hence AA TEST