Tìm x biết ( 5/3 - x ) : 2/5 = 3
Tìm x biết :
x + 4/5 = 4/5 + ( 3/7 + 3/5 ) 5/7 + x/35 = 4/5
x < 3/4 + 2 2/3 + 1 < x < 5/6 + 4
x< 5/6 - 3/4 2/3 < x < 2 - 5/6
a: =>x=3/7+3/5=15/35+21/35=36/35
b: =>x/35=4/5-5/7=28/35-25/35=3/35
=>x=3
c: =>x<3/4+8/4=11/4
=>\(x\in\left\{0;1;2;3\right\}\)
d: =>5/3<x<5/6+24/6=29/6
=>\(x\in\left\{2;3;4\right\}\)
e: =>x<10/12-9/12=1/12
=>x=0
f: =>2/3<x<12/6-5/6=7/6
=>x=1
Tìm x biết
-5(x+1/5)-1/2(x-2/3)=3/2x-5/6
3(x-1/2)-5(x+3/5)=-x+1/5
Tìm x,biết:
a)-5×(x+1/5)-1/2×(x-2/3)=3/2x-5/6
b)3×(x-1/2)-5(x+3/5)=-x+1/5
Tìm x biết: [3(x+1)-2(x+3)]^3+[2(x+3)-x+5]^3+[x-5-3(x+1)]^3=0
bài 1 :tìm x , biết :
(x-7)^ x+1(x-7)^x+11=0
bài 2 :tìm x , biết :
a,|2x-3| > 5 c,|3x-1| ≤ 7 d,|3x-5| + |2x+3| = 7
bài 3 :
a,tính tổng S = 1 + 5^2 + 5^4 + ....... + 5^200.
b,so sánh 2^30 + 3^30 + 4^30 và 3.24^10
1. Tìm x biết :
a) 3 mũ 2 nhân 2 mũ 5 - ( 3 nhân 6 mũ 2 - x ) = 120
b) ( x + 3 ) nhân 2 mũ 3 - 2 mũ 2 nhân 5 = 2 mũ 2 nhân 3 nhân 5
2. Tìm x biết :
a) 5 mũ x -1 - 13 = 612
b) 5 mũ x nhân 5 mũ 3 = 125
Bài 2
a) x=5
b)x=1
Tìm x,Biết
2.x+3=8
x:5-2=3
x:7-2=19
(x+3)x2=18
20-(x+3)=5
\(2x+3=8\)
\(\Rightarrow2x=8-3\)
\(\Rightarrow2x=5\)
\(\Rightarrow x=\dfrac{5}{2}\)
\(x:5-2=3\)
\(\Rightarrow x:5=3+2\)
\(\Rightarrow x:5=5\)
\(\Rightarrow x=5\cdot5\)
\(\Rightarrow x=25\)
\(x:7-2=19\)
\(\Rightarrow x:7=19+2\)
\(\Rightarrow x:7=21\)
\(\Rightarrow x=21\cdot7\)
\(\Rightarrow x=147\)
Mình chưa rõ đề
\(20-\left(x+3\right)=5\)
\(\Rightarrow-x-3=5-20\)
\(\Rightarrow-x-3=-15\)
\(\Rightarrow-x=-15+3\)
\(\Rightarrow-x=-12\)
\(\Rightarrow x=12\)
1. tìm x biết (3/1*3 + 3/3*5 + 3/5*7 +......+ 3/97*99) - x : 3/2 = 7/3
2. tìm số tự nhiên x,y biết (x-y)^2015 = 5^2015 và phân số x/y rút gọn được thành 4/3
1.
\(\left(\frac{3}{1\times3}+\frac{3}{3\times5}+\frac{3}{5\times7}+...+\frac{3}{97\times99}\right)-x:\frac{3}{2}=\frac{7}{3}\\
\left(\frac{2}{1\times3}+\frac{2}{3\times5}+\frac{2}{5\times7}+...+\frac{2}{97\times99}\right):\frac{3}{2}-x:\frac{3}{2}=\frac{7}{3}\\\left[\left(1-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+...+\frac{1}{97}-\frac{1}{99}\right)-x\right]:\frac{3}{2}=\frac{7}{3}\\
\left(1-\frac{1}{99}\right)-x=\frac{7}{3}\times\frac{3}{2}\\
\frac{98}{99}-x=\frac{7}{2}\\
x=\frac{98}{99}-\frac{7}{2}=\frac{-497}{198}\)
2.\(\frac{x}{y}=\frac{4}{3}\Rightarrow\hept{\begin{cases}x=4a\\y=3a\\x-y=4a-3a=a\end{cases}}\\ \left(x-y\right)^{2015}=5^{2015}\Rightarrow x-y=5\\ \Rightarrow a=5\Rightarrow\hept{\begin{cases}x=4\times5=20\\y=3\times5=15\end{cases}}\)
1.
(31×3+33×5+35×7+...+397×99)−x:32=73(21×3+23×5+25×7+...+297×99):32−x:32=73[(1−13+13−15+15−17+...+197−199)−x]:32=73(1−199)−x=73×32
Tìm x biết -5.[x+(1/5)]-(1/2).[x-(2/3)]=(3/2).x-(5/6)
Tìm x biết
1) 2.(x +5)+3.(x+7)=41. 6) 7. (x -1)+5.(3-x)=11.x-10
2) 5. ( x +6 ) +2.(x-3)=38. 7) 4. (2+x)+3(x-2)=12
3) 7.(5+x)+2.(x-10)=15. 8) 5. ( 2+x) +4.(3-x)=10x-15
4) 3. (x+4)+(8-2.x) =22. 9) 7.(x-2) +5.(3-x)=11x-6
5) 4. (x+5)+3.(7-x)=49. 10) 5.(3-x)+5.(x+4)=6+4x
1) 2(x + 5) + 3(x + 7) = 41
2x + 10 + 3x + 21 = 41
5x + 31 = 41
5x = 10
x = 2
6) 7(x - 1) + 5(3 - x) = 11x - 10
7x - 7 + 15 - 5x = 11x - 10
2x + 8 = 11x - 10
-9x = -18
x = 2
2) 5(x + 6) + 2(x - 3) = 38
5x + 30 + 2x - 6 = 38
7x + 24 = 38
7x = 14
x = 2
7) 4(2 + x) + 3(x - 2) = 12
8 + 4x + 3x - 6 = 12
7x + 2 = 12
7x = 10
x = 10/7
3) 7(5 + x) + 2(x - 10) = 15
35 + 7x + 2x - 20 = 15
9x + 15 = 15
9x = 0
x = 0
8) 5(2 + x) + 4(3 - x) = 10x - 15
10 + 5x + 12 - 4x = 10x - 15
x + 22 = 10x - 15
9x = 37
x = 37/9
4) 3(x + 4) + (8 - 2x) = 22
3x + 12 + 8 - 2x = 22
x + 20 = 22
x = 2
9) 7(x - 2) + 5(3 - x) = 11x - 6
7x - 14 + 15 - 5x = 11x - 6
2x + 1 = 11x - 6
-9x = -7
x = 7/9
5) 4(x + 5) + 3(7 - x) = 49
4x + 20 + 21 - 3x = 49
x + 41 = 49
x = 8
10) 5(3 - x) + 5(x + 4) = 6 + 4x
15 - 5x + 5x + 20 = 6 + 4x
35 = 6 + 4x
4x = 29
x = 29/4
1) 2(x + 5) + 3(x + 7) = 41
2x + 10 + 3x + 21 = 41
5x + 31 = 41
5x = 41 - 31
5x = 10
x = 10 : 5
x = 2
2) 5(x + 6) + 2(x - 3) = 38
5x + 30 + 2x - 6 = 38
7x + 24 = 38
7x = 38 - 24
7x = 14
x = 14 : 7
x = 2
3) 7(5 + x) + 2(x - 10) = 15
35 + 7x + 2x - 20 = 15
9x + 15 = 15
9x = 15 - 15
9x = 0
x = 0
4) 3(x + 4) + (8 - 2x) = 22
3x + 12 + 8 - 2x = 22
x + 20 = 22
x = 22 - 20
x = 2
5) 4(x + 5) + 3(7 - x) = 49
4x + 20 + 21 - 3x = 49
x + 41 = 49
x = 49 - 41
x = 8
6) 7(x - 1) + 5(3 - x) = 11x - 10
7x - 7 + 15 - 5x = 11x - 10
2x - 11x + 8 = -10
-9x = -10 - 8
-9x = -18
x = -18 : (-9)
x = 2
7) 4(2 + x) + 3(x - 2) = 12
8 + 4x + 3x - 6 = 12
7x + 2 = 12
7x = 12 - 2
7x = 10
x = 10/7
8) 5(2 + x) + 4(3 - x) = 10x - 15
10 + 5x + 12 - 4x = 10x - 15
10x - 15 = x + 22
10x - x = 22 + 15
9x = 37
x = 37/9
9) 7(x - 2) + 5(3 - x) = 11x - 6
7x - 14 + 15 - 5x = 11x - 6
11x - 6 = 2x + 1
11x - 2x = 1 + 6
9x = 7
x = 7/9
10) 5(3 - x) + 5(x + 4) = 6 + 4x
15 - 5x + 5x + 20 = 6 + 4x
6 + 4x = 35
4x = 35 - 6
4x = 29
x = 29/4