23 x X [ ( 12 x X + 39 ) ] : 3 = 23 + 40 x 115
23x[(12 x X+39):3] =23+40 x 115
Ta có: 23. [(12.X+39):3] = 4623
\(\Rightarrow\)(12.X+39):3 = 201
\(\Rightarrow\)12.X+39 = 603
\(\Rightarrow\)12.X = 564
\(\Rightarrow\)X = 47
23*[(12*x+39):3]=23+40*115
23 * [ ( 12 * x + 39 ) : 3 ] = 23 + 40 * 115
23 x [ ( 12 x x + 39 ) : 3 ] = 4623
( 12 x x + 39 ) : 3 = 4623 : 23
( 12 x x + 39 ) : 3 = 201
12 x x + 39 = 201 x 3
12 x x + 39 = 603
12 x x = 603 - 39
12 x x = 564
x = 564 : 12
x = 47
k mik nha các bn
Bài4:Tìm x:
a. 124 + (118 – x) = 217 b. 7x – 8 = 713 c. x- 36:18 = 12 d. (x- 36):18 = 12 e. (x-47) -115 = 0 f. 315 + (146 – x) = 401 | g. (6x – 39 ) : 3 = 201 h. 23 + 3x = 56 : 53 i. 5x + x = 39 – 311:39 j. 7x – x = 521 : 519 + 3.22 - 70 k. 7x – 2x = 617: 615 + 44 : 11 l. 0 : x = 0 | m. 3x = 9 n. 4x = 64 o. 2x = 16 p. 9x- 1 = 9 q. x4 = 16 r. 2x : 25 = 1 |
Bài4:Tínhnhanh
1. 58.75 + 58.50 – 58.25 2. 27.39 + 27.63 – 2.27 3. 128.46 + 128.32 + 128.22 4. 87.23 + 13.93 + 70.87
| 5. 12.35 + 35.182 – 35.94 6. 48.19 + 48.115 + 134.52 7. 27.121 – 87.27 + 73.34 8. 136.23 + 136.17 – 40.36 9. 125.98 – 125.46 – 52.25 | 10. 17.93 + 116.83 + 17.233 11. 5.23 + 35.41 + 64.65 12. 29.87 – 29.23 + 64.71 13. 19.27 + 47.81 + 19.20
|
b: Ta có: 7x-8=713
nên 7x=721
hay x=103
c: Ta có: x-36:18=12
nên x-2=12
hay x=14
d: Ta có: (x-36):18=12
nên x-36=216
hay x=252
a. 124 + (118 – x) = 217
118 - x = 93
- x = - 25
x = 25
b. 7x – 8 = 713
7x =721
x =103
c. x- 36:18 = 12
x- 2 =12
x =14
d. (x- 36):18 = 12
x-36 = 216
x = 252
e. (x-47) -115 = 0
x-47 = 115
x = 162
f. 315 + (146 – x) = 401
146-x =86
-x = -60
x = 60
g. (6x – 39 ) : 3 = 201
6x - 39 = 603
6x = 642
x = 107
h. 23 + 3x = 56 : 53
23 +3x = 125
3x = 102
x=34
23 x 5-[115-(12-5)2 ]
\(\dfrac{3}{4}\) x 36 + 75% x 23 + \(\dfrac{75}{100}\) + 0,75 x 40
= ..... x 36 + ....... x 23 + ..... + 0,75 x 40
= ..... x ( 36 + 23 + 1 + ..... )
= ..... x 100
= .....
Tìm x :
a) 2(x - 23) - (x - 43) = 96 - 115
b) 2(x - 12) + 13 = x + (- 14)
e) x-43=(57-x)-50 f)-(x-3+84)=(x+70-71)-5 g)2(x-23)-(x-43)=96-115 h)2(x-12)+13=x+(-14)
e)x-43=(57-x)-50.
Suy ra x-43=57-x-50=57-50-x=7-x
Suy ra x-43+x=7. suy ra2x=7+43=50
Nên x=50:2=25
f)-(x-3+84)=(x+70-71)-5.
Suy ra -x+3-84=x-1-5=x-6
Suy ra -x-81=x-6. suy ra -x-81+6=x.suy ra-x-75=x
Suy ra -x-x=75 nên -2x=75 suy ra x=-75/2=-37.5
g)2(x-23)-(x-43)=96-115.
Suy ra 2x-46-x+43=-19,
suy ra 2x-x-46+43=-19,
suy ra x-3=-19
Nên x=-19+3=-16
h)2(x-12)+13=x+(-14)=x-14.
Suy ra 2x-24+13=x-14,
suy ra 2x-11=x-14,
suy ra 2x-11+14=x=2x+3,
suy ra x-2x=3 nên -x=3
vậy x=-3
e)x-43=(57-x)-50. Suy ra x-43=57-x-50=57-50-x=7-x
Suy ra x-43+x=7. suy ra2x=7+43=50
Nên x=50:2=25
f)-(x-3+84)=(x+70-71)-5. Suy ra -x+3-84=x-1-5=x-6
Suy ra -x-81=x-6. suy ra -x-81+6=x.suy ra-x-75=x
Suy ra -x-x=75 nên -2x=75 suy ra x=-75/2=-37.5
29 x 87 - 29 x 23 + 64 x 71
48 x 19 + 48 x 115 + 134 x 52
27 x 121 - 87 x 27 + 73 x 34
125 x 98 - 125 x 46 - 52 x 25
136 x 23 + 136 x 17 - 40 x 36
làm nhanh nhanh lên hộ mình vs nhé, cảm ơn