Share
Toan lớp 6 tìm x ai giải hok
Question
Leave an answer
Diễm Kiều
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Answers ( )
a, (x – 10).11 = 22
x – 10 = 22 : 11
x – 10 = 2
x = 2 + 10
x = 12
b, 2x + 15 = -27
2x = -27 – 15
2x = – 42
x = (-42) : 2
x = – 21
c, -765 – (305 + x) = 100
– (305 + x) = 100 + 765
– (305 + x) = 865
305 + x = -865
x = -865 – 305
x= – 1170
d, 2x: 4 = 162
x= 16 x 42
x= 642
x= 26
⇒ x = 6
e, 25< $5^{x}$ < 3125
=> $5^{2}$< $5^{x}$ < $5^{5}$
=> x = 3 hoặc x = 4
f, (17x – 25): 8 + 65 = 92
(17x – 25): 8 + 65 = 81
(17x – 25): 8 = 81 – 65
(17x – 25): 8 = 16
17x – 25 = 16.8
17x – 25 = 128
17x = 128 + 25
17x = 153
x = 153 : 17
x = 9
g, 5.(12 – x ) – 20 = 30
5.(12 – x) = 30 + 20
5.(12 – x) = 50
12 – x = 50 : 5
12 – x = 10
x = 12 – 10
x = 2
h, (50 – 6x).18 = $2^{3}$ .$3^{2}$ .5
(50 – 6x).18 = 8.9.5
(50 – 6x).18 = 360
50 – 6x = 360 : 18
50 – 6x = 20
6x = 50 – 20
6x = 30
x = 30 : 6
x = 5
i, 128 – 3(x + 4) = 23
3.(x + 4) = 128 – 23
3.(x + 4) = 105
x + 4 = 105 : 3
x + 4 = 35
x = 35 – 4
x = 31
k, [( 4x + 28 ).3 + 55] : 5 = 35
(4x + 28).3 + 55 = 35.5
(4x + 28).3 + 55 = 175
(4x + 28).3 = 175 – 55
(4x + 28).3 = 120
4x + 28 = 120 : 3
4x + 28 = 40
4x = 40 – 28
4x = 12
x = 12 : 4
x = 3
l, (3x – $2^{4}$ ) .$7^{3}$ = 2.$7^{4}$
3x – $2^{4}$= 2.$7^{4}$: $7^{3}$
3x – $2^{4}$= 2.($7^{4}$: $7^{3}$)
3x – $2^{4}$= 2.7
3x – 16 = 14
3x = 14 + 16
3x = 30
x = 30 : 3
x = 15
m, 43 + (9 – 21) = 317 – (x + 317)
43 + (–12) = 317 – x – 317
43 – 12 = 317 – 317 – x
31 = – x
– x = 31
x = – 31
n, (x + 1) + (x + 2) + (x+3) +…+ (x + 100) = 7450
x + 1 + x + 2 + x + 3 + … + x + 100 = 7450
(x + x + x + … + x) + (1 + 2 + 3 + … + 100) = 7450
100.x + (100 + 1).100 : 2 = 7450
100.x + 5050 = 7450
100.x = 7450 – 5050
100.x = 2400
x = 2400 : 100 = 24
a, (x – 10) . 11 = 22
x – 10 = 22 : 11
x – 10 = 2
x = 2 + 10
x = 12
b, 2x + 15 = -27
2x = -27 – 15
2x = – 42
x = (-42) : 2
x = – 21
c, -765 – (305 + x) = 100
– (305 + x) = 100 + 765
– (305 + x) = 865
305 + x = -865
x = -865 – 305
x= – 1170
d, 2x : 4 = 162
x = 16 x 42
x = 642
x = 26
⇒ x = 6
e, 25< 5^x < 3125
=>5^2 < 5^x < 5^5
=> x = 3 hoặc x = 4
f, (17x – 25) : 8 + 65 = 92
(17x – 25) : 8 + 65 = 81
(17x – 25) : 8 = 81 – 65
(17x – 25) : 8 = 16
17x – 25 = 16 . 8
17x – 25 = 128
17x = 128 + 25
17x = 153
x = 153 : 17
x = 9
g, 5 . (12 – x ) – 20 = 30
5 . (12 – x) = 30 + 20
5 . (12 – x) = 50
12 – x = 50 : 5
12 – x = 10
x = 12 – 10
x = 2
Sorry mình làm đc nhiêu đây thôi!
Để tìm câu trả lời chính xác các em hãy tham khảo các dạng toán tìm x lớp 6 các nguồn hoc24.vn, lazi.vn, hoidap247.com để thầy cô và các chuyên gia hỗ trợ các em nhé!