Page 60 - Grade 10 C.Math

pbfx/0f 2
prfO / Jof;sf] of]ukmn 28 ;]=ld= tyf jj|m ;txsf] If]qkmn 462 ju{ ;]=ld= ePsf] Pp6f
a]ngfsf] k'/f ;txsf] If]qkmn lgsfNg'xf];\ .

;dfwfg

oxfF, a]ngfsf] prfO (h) / Jof; (d) sf] of]ukmn = 28 ;]=ld=
Curriculum Development Centre
jj|m ;txsf] If]qkmn (CSA) = 462 ju{ ;]=ld=
a]ngfsf] k'/f ;txsf] If]qkmn (TSA) = ?

lbOPsf]af6, a]ngfsf] prfO / Jof;sf] of]ukmn, h + d = 28 cm
cyjf, d = 28 - h....... (i)

jj|m ;txsf] If]qkmn (CSA) = 462 cm 2
cyjf πdh = 462 cm 2 h

;dLs/0f (i) / (ii) af6
d


cyjf, 28h – h = 147
2
cyjf, h – 28h + 147 = 0
2
cyjf, h – 7h – 21h + 147 = 0
2
cyjf, h(h-7) – 21(h – 7) = 0

cyjf, (h – 7)(h – 21) = 0
t;y{ h – 7 = 0 cyjf h — 21 = 0
t;y{ h = 7 cyjf, h= 21

ctM d = 28-7 =21 ;]=ld= cyjf, d = 28 – 21 = 7 ;]=ld=
cyjf, r = 10.5 ;]=ld= jf r = 3.5 ;]=ld= / h = 7 ;]=ld= jf h = 21 ;]=ld=

ca, r = 3.5 cm / h = 21 cm x'Fbf a]ngfsf] k'/f ;txsf] If]qkmn

ju{ ;]=ld=
= 22 × 24.5 ju{ ;]=ld=

=539 ju{ ;]=ld=

k'gM r = 10.5 ;]=ld= / h = 7 x'Fbf a]ngfsf] k'/f ;txsf] If]qkmn slt x'G5 < kTtf nufpg'xf];\ .

57 ul0ft, sIff – 10