x + 50 = 400: 2
(400-1^2)x(400-2^2)x...x(400-50^2)
ta có :(400-1^2).(400-2^2)..........(400-20^2)..... (400-50^2)
=(400-1^2).........(400-400)............(400-50^2)
=(400-1^2).........0...........(400-50^2)
=0
25 x 2 =
50 x 2 =
100 x 2 =
200 x 2 =
400 x 2 =
25 x 2 = 50
50 x 2 = 100
100 x 2 = 200
200 x 2 = 400
400 x 2 = 800
#)Trả lời :
25 x 2 = 50
50 x 2 = 100
100 x 2 = 200
200 x 2 = 400
400 x 2 = 800
#~Will~be~Pens~#
20 x X : 50 : 40 + 350 = 400
mn có biết tại sao x = 50 + y=50 lại bằng 400 ko
Bài 1 : tính nhanh
a ) ( a - b ) - ( c - b ) -a
b ) - ( 300 - 400 ) + ( 300 - 400 ) + 100
bài 2 :tìm x biết
a ) 4x - 20 = 50 - ( 30 - 3x )
b ) 100 - ( - 5X ) = 40 - ( - 4x +10 )
c ) ( - 50 ) + ( - 7x ) = 100 - 8x
a) (a-b)-(c-b)-a=a-b-c+b-a=(a-a)+(b-b)-c=0+0-c=-c
1)
a) (a-b) - (c-b) - a= a - b - c + b - a = -c
b) -(300 - 400) + (300 - 400) + 100 = 100
2) a) 4x - 20 = 50 - ( 30 -3x)
4x - 20 = 50 - 30 + 3x
4x - 3x = 50 - 30 + 20= 40
x = 40
b) 100 - (-5x) = 40 - (-4x +10)
100 + 5x = 40 + 4x -10
5x - 4x = 40 - 10 -100
x = -70
c) (-50) + (-7x) = 100 - 8x
-7x + 8x = 100 + 50
x = 150
Bài 1.
a) \(\left(a-b\right)-\left(c-b\right)-a\)
\(=a-b-c+b-a\)
\(=\left(a-a\right)+\left(-b+b\right)-c\)
\(=-c\)
b)\(-\left(300-400\right)+\left(300-400\right)+100\)
\(=-300+400+300-400+100\)
\(=\left(-300+300\right)+\left(400-400\right)+100\)
\(=100\)
Bài 2.
a)\(4x-20=50-\left(30-3x\right)\)
\(\Leftrightarrow4x-20=50-30+3x\)
\(\Leftrightarrow4x-20=20+3x\)
\(\Leftrightarrow x=40\)
Vậy x = 40
b)\(100-\left(-5x\right)=40-\left(-4x+10\right)\)
\(\Leftrightarrow100+5x=40+4x-10\)
\(\Leftrightarrow x=-70\)
Vậy x = -70
c)\(\left(-50\right)+\left(-7x\right)=100-8x\)
\(\Leftrightarrow-50-7x=100-8x\)
\(\Leftrightarrow x=150\)
Vậy x = 150
Linz
x + 50 + 100 = 500 + 400
x + 50 + 100 = 500 + 400
x + 50 + 100 = 900
x = 900 - 100 - 50
x = 750
k mk mk k lại
x + 400 = 500 - 100
x + 10 = 50
a)x+400=500-100
x+400=400
x=400-400
x=0
b)x+10=50
x=50-10
x=40
x + 400 = 500 - 100
x + 400 = 400
x = 400 - 400
x = 0
x + 10 = 50
x = 50 -10
x = 40
x+400=500-100
x+400=400
x =400-400
x =0
x+10=50
x =50-10
x =40
tk mk nha
Tính
a) 1,5678 : 2,34 x 50 - 65
b) 25,76 - (43 - 400 x 0,1 - 300 x 0.01)
a) 1,5678 : 2,34 x 50 - 65
=0,67×50-65
=33,5-65
=-31,5
25,76 - (43 - 400 x 0,1 - 300 x 0.01)
=25,75-(43-40+3)
=25,75-(3+3)
=25,75-6
=19,75
Sắp xếp các ô theo thứ tự tăng dần
40 : 20% + 30 : 10% | 47,5 : (45% - 20%) |
650 x 50% + 207 : 36% | 1000 x 45% + 60 : 12% |
(20% + 30%0 x 360 | 68% : 2 x 500 |
25% x 30 x 20 | 120 : (20% x 3) |
600 x (75% :1,5) | 400 : 40% - 100 : 50% |
Làm hộ mìn nha,mìn tick cho