Matematika

MATEMATIKA

MAVZU: IFODALARNI SODDALASHTIRISH
5- sinf
QAVSLARNI OCHISH QOIDASI
Ko‘paytirishning taqsimot qonunlari:
(a + b) • c = a • c + b • c

(a – b) • c = a • c – b • c
UMUMIY KO‘PAYTUVCHINI QAVSDAN TASHQARIGA CHIQARISH
(a + b) • c = a • c + b • c
(a – b) • c = a • c – b • c
Tengliklarning chap va o‘ng qismidagi ifodalarning o‘rnini almashtiramiz:
a • c + b • c = (a + b) • c
a • c – b • c = (a – b) • c
MISOLLAR
1) 9a + 4a ifodada umumiy ko‘paytuvchi a ni qavsdan tashqariga chiqaring.
9a + 4a = (9 + 4) a = 13a
2) Umumy ko‘paytuvchini qavsdan tashqariga chiqarib hisoblang:

• 28 • 6 + 22 • 6

b) 36 • 8 – 26 • 8

= (28 + 22) • 6 = 50 • 6 = 300
= (36 – 26) • 8 = 10 • 8 = 80
MISOLLAR
3) Tenglamani yeching: 4x +5x + 21 = 39.
Yechish: 4x + 5x = (4 +5)x = 9x
9x + 21 = 39
9x = 39 – 21
9x = 18
x = 18 : 9
x = 2

268- masala

Qavslarni oching:
a) 5 • (x + 3) b) (6 + x) • 2 d) 4 • (x - 8)
e) (y - 7) • 3 f) 12 • (c + 8) g) (4 - y ) • 5
Yechish:

• 5 •(x + 3) = 5x + 15

b) (6 + x) • 2 = 12 + 2x
d) 4 • (x - 8) = 4x – 32
e) (y - 7) • 3 = 3y - 21

269- masala

Ifodani soddalashtirib uning qiymatini toping:

• 23a + 13a, bunda a = 9

b) 34b - 17b, bunda b = 19

Yechish:
b) 34b – 17b = (34 – 17)b = 17b
b = 19, 17b = 17 • 19 = 323

271- masala

Ifodadagi umumiy ko‘paytuvchini qavsdan tashqariga
chiqarib, uning qiymatini toping:
a) 81 • 21 + 19 • 21
b) 252 • 80 - 252 • 70
d) 201 • 91 + 112 • 91
e) 696 • 24 - 696 • 14
f) 53 • 17 + 32 • 17
g) 23 • 99 - 23 • 51

YECHISH

b) 252 • 80 - 252 • 70 = 252 • (80 – 70)=252 •10=2520
d) 201 • 91 + 112 • 91=91 •(201 + 112)=91•313=28483
e) 696 • 24 - 696 • 14 =
f) 53 • 17 + 32 • 17 =
g) 23 • 99 - 23 • 51 =
696 •(24 -14)= 696 •10=6960
17 •(53+32) = 17 • 85 = 1445
23 •(99 - 51) = 23 • 48 = 1104

272- masala

Ifodadagi umumiy ko‘paytuvchini qavsdan tashqariga chiqarib, uni ko‘paytma ko‘rinishida ifodalang:
a) 15x + 34x b) 49x - 24x d) 100x - x
e) 89b - 39b f ) 999x + x g) 597p - 197p
Yechish:
d) 100x – x = (100-1)x = 99x
e) 89b - 39b = (89 – 39)b = 50b
f) 999x + x = ( 999 + 1)x = 1000x
g) 597p - 197p = ( 597 – 197)p = 400p

275- masala

Agar to‘g‘ri to‘rtburchakning perimetri 390 cm bo‘lsa, 1-rasmdagi ma’lumotlardan foydalanib uning tomonlarini toping.
5x
8x
Yechish:
P = 2(a+b)
a = 5x, b = 8x
P = 2 •(5x + 8x) = 2 • x •(5 + 8)=
= 2 • x •13 = 26x
Javob: 26x

276- masala

Ifodani soddalashtiring:
a) 5x + 23 + 4x + 1 b) 12y + 31 + 34y + 8
d) 72 + 23p + 30 + 44p + 1 e) 55d + 23 + 45 + 45d
Yechish:

• 5x + 23 + 4x + 1 =

b) 12y + 31 + 34y + 8
d) 72 + 23p + 30 + 44p + 1 =
e) 55d + 23 + 45 + 45d =

23 + 1
+ (5 + 4)x
= 24 + 9x
+ 46y
103 + 67p
68 + 100d
= 39

Mustaqil bajarish uchun topshiriqlar:

Mustaqil bajarish uchun topshiriqlar:

Darslikdagi 277-, 278-, 279-,

280- masalalarni yechish (61- bet).