1. (627- 138) : ( 3 x X :2) = 163
2. (X-1)x3+ 3/20 +3/13+3/2015/5+5/20+5/13+5/20+5/2015
x.3+3/20+3/15+3/2015/5+5/20+5/13+5/2015
tìm x biết
a, -12 ( x - 5 ) + 7 ( 3 - x ) = 2015
b, 20 ( x - 4 ) - 5 ( x + 3 ) - 15x = 20
c, I 2x - 5 I = 13
d, ( x + 3) ( x - 7 ) < 0
-3 x 1 x 6 x 2 x 5 x 12 x 13 x16 x 16 - 15 x 20
-1 x 2 x3 x 4 x3 x-3 x6 - 4 x 8 - 5 x 100
1) 2³ .x -5² x = 2( 5² + 2² ) -33. 2) 15÷ ( x +2) = (3³ +3) ÷1
3) 20÷ (x +1) = (5² +1 ) ÷13. 4) 320÷ ( x -1 ) = (5³ - 5² ) ÷4 +15
5) 240 ÷ ( x -5 ) = 2² .5² -20. 6) 70 ÷ ( x -3) = ( 3⁴ -1) ÷ 4 - 10
Giúp mình với mình Tối nay mình đi học rồi
1) \(2^3\times x-5^2\times x=2\times\left(5^2+2^2\right)-33\)
\(x\times\left(2^3-5^2\right)=2\times\left(25+4\right)-33\)
\(x\times\left(8-25\right)=2\times29-33\)
\(x\times-17=25\)
\(x=-\dfrac{25}{17}\)
2) \(15\div\left(x+2\right)=\left(3^3+3\right)\div1\)
\(15\div\left(x+2\right)=\left(27+3\right)\div1\)
\(15\div\left(x+2\right)=30\div1\)
\(15\div\left(x+2\right)=30\)
\(x+2=\dfrac{1}{2}\)
\(x=-\dfrac{3}{2}\)
3) \(20\div\left(x+1\right)=\left(5^2+1\right)\div13\)
\(20\div\left(x+1\right)=\left(25+1\right)\div13\)
\(20\div\left(x+1\right)=26\div13\)
\(20\div\left(x+1\right)=2\)
\(x+1=20\div2\)
\(x+1=10\)
\(x=9\)
4) \(320\div\left(x-1\right)=\left(5^3-5^2\right)\div4+15\)
\(320\div\left(x-1\right)=\left(125-25\right)\div4+15\)
\(320\div\left(x-1\right)=100\div4+15\)
\(320\div\left(x-1\right)=25+15\)
\(320\div\left(x-1\right)=40\)
\(x-1=8\)
\(x=9\)
5) \(240\div\left(x-5\right)=2^2\times5^2-20\)
\(240\div\left(x-5\right)=4\times25-20\)
\(240\div\left(x-5\right)=100-20\)
\(240\div\left(x-5\right)=80\)
\(x-5=30\)
\(x=35\)
6) \(70\div\left(x-3\right)=\left(3^4-1\right)\div4-10\)
\(70\div\left(x-3\right)=\left(81-1\right)\div4-10\)
\(70\div\left(x-3\right)=80\div4-10\)
\(70\div\left(x-3\right)=20-10\)
\(70\div\left(x-3\right)=10\)
\(x-3=7\)
\(x=10\)
123-5.(x+4)=38
10+2x=2.(32-1)
2.x-138=23.32
[102+(28-2x)]:20-5=1
231-(x-6)=1339:13
123-5.(x+4)=38
5(x+4)=123-38
5(x+4)=85
x+4=85:5
x+4=17
x=17-4
x=13
10+2x=2.(32-1)
10+2x=2.(9-1)
10+2x=2.8
2x=16-10
2x=6
x=6:2
x=3
2.x-138=23.32
2.x-138=72
2.x=72+138
2.x=210
x=210:2
x=105
[102+(28-2x)]:20-5=1
(102+28-2x):20=6
130-2x=120
2x=130-120
2x=10
x=10:2
x=5
231-(x-6)=1339:13
231-(x-6)=103
x-6=231-103
x-6=128
x=128+6
x=134
123-5.(x+4)=38
5.(x+4)=123-38
5.(x+4)=85
(x+4)=85/5
x+4=17
x=17-4
x=13
10 + 2x = 2(32 - 1)
=> 10 + 2x = 2(9 - 1)
=> 10 + 2x = 2.8
=> 10 + 2x = 16
=> 2x = 16 - 10
=> 2x = 6
=> x = 6/2
=> x = 3
Bài 1. Tìm x biết
a, 2015 - 2 × X = 101
b, 7 - ( 11 + X - 13 ) : 2 và 2/3 = 2
c, 2012 - 5 × X = 17
d, 5 và 3/4 + ( X - 2 ) × 1/3 = 17 và 3/4
e, 12 × ( X - 5 ) + 73 = 20
Giải giúp mình nhé mình cầu xin các bạn 🙏🙏🙏
a, 2015 - 2 × X = 101
2 x X = 2015 - 101
2 x X = 1914
X = 1914 : 2
X = 957
1a. 2015 - 2 x X = 101
2 x X = 2015 - 101
X = 1914 : 2
X = 957
b. 7 - (11 + X - 13) : \(2\frac{2}{3}\)= 2
(11 + X - 13) : \(2\frac{2}{3}\) = 7 - 2
11 + X - 13 = 5 x \(2\frac{2}{3}\)
11 + X = \(\frac{40}{3}\)+ 13
X = \(\frac{79}{3}\)- 11
X = \(\frac{46}{3}\)
c. 2012 - 5 x X = 17
5 x X = 2012 - 17
X = 1995 : 5
X = 399
d. \(5\frac{3}{4}\)+ (X - 2) x \(\frac{1}{3}\)= \(17\frac{3}{4}\)
(X - 2) x \(\frac{1}{3}\) = \(17\frac{3}{4}\)- \(5\frac{3}{4}\)
X - 2 = 12 : \(\frac{1}{3}\)
X = 36 + 2
X = 38
e. 12 x (X - 5) + 73 = 20
12 x (X - 5) = 20 - 73
X - 5 = -53 : 12
X = \(\frac{-53}{12}\)+ 5
X = \(\frac{7}{12}\)
a )
2015 - 2 x X = 101
2 x X = 2015 - 101
2 x X = 1914
X = 1914 : 2
X = 957
b )
7 - ( 11 + X - 13 ) : \(2\frac{2}{3}\) = 2
( 11 + X - 13 ) : \(2\frac{2}{3}\) = 7 - 2
( 11 + X - 13 ) : \(2\frac{2}{3}\) = 5
11 + X - 13 = 5 x \(2\frac{2}{3}\)
11 + X - 13 = \(13\frac{1}{3}\)
X = \(13\frac{1}{3}\) + 13 - 11
X = \(15\frac{1}{3}\)
c )
2012 - 5 x X = 17
5 x X = 2012 - 17
5 x X = 1995
X = 1995 : 5
X = 399
d )
\(5\frac{3}{4}\) + ( X - 2 ) x \(\frac{1}{3}\) = \(17\frac{3}{4}\)
( X - 2 ) x \(\frac{1}{3}\) = \(17\frac{3}{4}+5\frac{3}{4}\)
( X - 2 ) x \(\frac{1}{3}\) = \(23\frac{1}{2}\)
X - 2 = \(23\frac{1}{2}\div\frac{1}{3}\)
X - 2 = 47
X = 47 + 2
X = 49
e ) Mình không làm đực câu này đâu
Học tốt nhé bạn !
1. -2/9 x 15/17 + -2/9 x 2/17
2. -5/3 x 6/5 + -7/9 x 3/10
3. 15/20 x 7/5 + -9/7 x -6/4
4.-25/13 x 5/19 + -25/13 x 14/19
5 -7/13 x 13/5 + -9/7 x 5/3
6. 27/35 x 5/9 - 2/7 x -7/5
7. 10/13 x 13/5 + {-9/5} x 10/3
8. 100/27 x 9/20 + 40% x 5/3
9. 1,5 x 5/12 + 1/4 x 3/4
10. 2 1/2 x 7/5 + {-9/10} x 2/3
11. X + 45% = 2 1/2 -5/3
12. 80% + X = -5/2 + 3/4
13. 4/25 - X =-5/2 + -3/10
1: =-2/9(15/17+2/17)=-2/9
2: \(=\dfrac{-6}{3}+\dfrac{-21}{90}\)
=-2-7/30=-67/30
3: \(=\dfrac{3}{4}\cdot\dfrac{7}{5}+\dfrac{9}{7}\cdot\dfrac{3}{2}\)
=21/20+27/14=417/140
4: =-25/13(5/19+14/19)=-25/13
5: =-7/5-45/21=-7/5-15/7=-124/35
1: =-2/9(15/17+2/17)=-2/9
2: =34⋅75+97⋅32=34⋅75+97⋅32
=21/20+27/14=417/140
4: =-25/13(5/19+14/19)=-25/13
5: =-7/5-45/21=-7/5-15/7=-124/35
Câu 1: So sánh :
a)27/13 và 2019/1009
b)1234/1201 và 9999/10000
Câu 2: Tìm x:
1/1×3+1/3×5+...+1/x(x+2)=20/41
Câu 3: Tính nhanh:
C=5/6+5/138+5/391+...5/3471+5/4450
tìm x biết 3+3/20+3/15+3/2015
5+5/20+5/15+5/2015=5/3