a/713:(2x+17)=23
b/(x+4/3)*7/4=5-7/6
a/317+(600-x)=517
b/325-(x+16)=425:17
c/25*(x-1)=0
d/713:(2x+17)=23
e/(x+a/3)*7/4=5-7/6
1, Tìm số nguyên x, biết:
a, x - 17 = 23
b, 2(x - 1) = 7 + (-3)
c, 4.(x + 5)3 - 7 = 101
d, 2x+1 .3 + 15 = 39
1)
\(x-17=23\\ \Rightarrow x=23+17\\ \Rightarrow x=40\)
2)
\(2\left(x-1\right)=7+\left(-3\right)\\ \Rightarrow2x-2=4\\ \Rightarrow2x=4+2\\ \Rightarrow2x=8\\ \Rightarrow x=4\)
3)
\(4\left(x+5\right)^3-7=101\\ \Rightarrow4\left(x+5\right)^3=101+7\\ \Rightarrow4\left(x+5\right)^3=108\\ \Rightarrow\left(x+5\right)^3=108\div4\\ \Rightarrow\left(x+5\right)^3=27\\ \Rightarrow\left(x+5\right)^3=3^3\\ \Rightarrow x+5=3\Rightarrow x=3-5\\ \Rightarrow x=-2\)
4)
\(2^{x+1}\times3+15=39\\ \Rightarrow2^{x+1}\times3=39-15\\ \Rightarrow2^{x+1}\times3=24\\ \Rightarrow2^{x+1}=24\div3\\ \Rightarrow2^{x+1}=8\)
\( \Rightarrow2^{2+1}=8\\\Rightarrow2^3=8\Rightarrow x=2 \)
a) x - 17 = 23
x = 23 + 17
x = 40
Vậy x = 40
b) 2 ( x - 1 ) = 7 + ( - 3 )
x - 1 = 4 : 2
x = 2 + 1
x = 3
Vậy x = 3
c) 4 ( x + 3 )^3 - 7 = 101
4 ( x + 3 )^3 = ( 101 + 7 ) : 4
( x + 3 )^3 = 3^3
⇒ x + 3 = 3
⇒ x = 0
Vậy x = 0
d) 2^{ x+ 1 } . 3 + 15 = 39
2^{ x + 1 } = ( 39 - 15 ) : 3
2^{ x + 1 } = 2{ 2 + 1 }
⇒ x + 1 = 2 + 1
⇒ x = 2
Vậy x = 2
a. 2/3x-1/2=1/10
b. 39/7:x=13
c. (14/5x-50):2/3=51
d. (x+1/2)(2/3-2x)=0
e. 2/3x-1/2x=5/12
g. (x.44/7+3/7)11/5-3/7=-2
h. x.13/4+(-7/6)x-5/3=5/12
i.93/17:x+(-4/17):x+22/7:52/3=4/11
j. 17/2-|2x-3/4|=-7/4
k. (x+1/5)^2+17/25=26/25
l. -32/27-(3x-7/9)^3=-24/27
a) \(\dfrac{2}{3}x-\dfrac{1}{2}=\dfrac{1}{10}\)
\(\dfrac{2}{3}x=\dfrac{1}{10}+\dfrac{1}{2}=\dfrac{3}{5}\)
\(x=\dfrac{3}{5}:\dfrac{2}{3}=\dfrac{9}{10}\)
b) \(\dfrac{39}{7}:x=13\)
\(x=\dfrac{\dfrac{39}{7}}{13}=\dfrac{3}{7}\)
c) \(\left(\dfrac{14}{5}x-50\right):\dfrac{2}{3}=51\)
\(\dfrac{14}{5}x-50=51\cdot\dfrac{2}{3}=34\)
\(\dfrac{14}{5}x=34+50=84\)
\(x=\dfrac{84}{\dfrac{14}{5}}=30\)
d) \(\left(x+\dfrac{1}{2}\right)\left(\dfrac{2}{3}-2x\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{2}=0\\\dfrac{2}{3}-2x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{1}{2}\\x=\dfrac{1}{3}\end{matrix}\right.\)
e) \(\dfrac{2}{3}x-\dfrac{1}{2}x=\dfrac{5}{12}\)
\(\dfrac{1}{6}x=\dfrac{5}{12}\)
\(x=\dfrac{5}{12}:\dfrac{1}{6}=\dfrac{5}{2}\)
g) \(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\dfrac{11}{5}-\dfrac{3}{7}=-2\)
\(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\cdot\dfrac{11}{5}=-2+\dfrac{3}{7}=-\dfrac{11}{7}\)
\(x\cdot\dfrac{44}{7}+\dfrac{3}{7}=-\dfrac{11}{7}:\dfrac{11}{5}=-\dfrac{5}{7}\)
\(\dfrac{44}{7}x=-\dfrac{5}{7}-\dfrac{3}{7}=-\dfrac{8}{7}\)
\(x=-\dfrac{8}{7}:\dfrac{44}{7}=-\dfrac{2}{11}\)
h) \(\dfrac{13}{4}x+\left(-\dfrac{7}{6}\right)x-\dfrac{5}{3}=\dfrac{5}{12}\)
\(\dfrac{25}{12}x-\dfrac{5}{3}=\dfrac{5}{12}\)
\(\dfrac{25}{12}x=\dfrac{5}{12}+\dfrac{5}{3}=\dfrac{25}{12}\)
\(x=1\)
Mỏi tay woa bn làm nốt nha!!
a,4x-10=0 b, 7-3x=9-x c, 2x-(3-5x) = 4(x+3)
d, 5-(6-x)=4(3-2x) e, 4(x+3)=-7x+17 f, 5(x-3) - 4=2(x-1)+7
g, 5(x-3)-4=2(x-1)+7 h,4(3x-2)-3(x-4)=7x+20
`a,4x-10=0 `
`<=> 4x=10`
`<=>x=10/4`
`<=>x=5/2`
`b, 7-3x=9-x `
`<=>-3x+x=9-7`
`<=>-2x=2`
`<=>x=-1`
`c, 2x-(3-5x) = 4(x+3)`
`<=>2x-3+5x=4x+12`
`<=>2x+5x-4x=12+3`
`<=>3x=15`
`<=>x=5`
`d, 5-(6-x)=4(3-2x) `
`<=>5-6+x=12-8x`
`<=>x+8x=12-5+6`
`<=>9x=13`
`<=>x=13/9`
`e, 4(x+3)=-7x+17 `
`<=>4x+12=-7x+17`
`<=>4x+7x=17-12`
`<=>11x=5`
`<=>x=5/11`
`f, 5(x-3) - 4=2(x-1)+7`
`<=>5x-15-4=2x-2+7`
`<=>5x-2x=15+4-2+7`
`<=>3x=24`
`<=>x=8`
`g, 5(x-3)-4=2(x-1)+7 `
`<=>5x-15-4=2x-2+7`
`<=>5x-2x=15+4-2+7`
`<=>3x=24`
`<=>x=8`
`h,4(3x-2)-3(x-4)=7x+20`
`<=>12x-8-3x+12=7x+20`
`<=>12x-3x-7x=20+8+12`
`<=>2x=40`
`<=>x=20`
Bài 1: thực hiện phép tính
a, (3/8 + -3/4 + 7/12) : 5/6 + 1/2
b, -7/3. 5/9+ 4/9. (-3/7)+ 17/7
c,117/13 - (2/5 + 57/13)
d, 2/3 - 0,25 : 3/4 + 5/8 .4
Bài 2: tìm x biết
a, 2/3 x - 1/2 = 1/10
b, -2/3 -1/3 (2x -5) = 3/2
c, (3x -1) (-1/2 x + 7) =0
d, 17/2 - | 2x - 3/4 | =-7/4
e, (x + 1/25) +17/25 = 26/25
\(a,\left(\frac{3}{8}+-\frac{3}{4}+\frac{7}{12}\right):\frac{5}{6}+\frac{1}{2}\)
= \(\left(-\frac{3}{8}+\frac{7}{12}\right):\frac{5}{6}+\frac{1}{2}\)
= \(\frac{5}{24}:\frac{5}{6}+\frac{1}{2}\)
= \(\frac{1}{4}+\frac{1}{2}\)
= \(\frac{3}{4}\)
b)\(-\frac{7}{3}.\frac{5}{9}+\frac{4}{9}.\left(-\frac{3}{7}\right)+\frac{17}{7}\)
=\(-\frac{35}{27}+\left(-\frac{4}{21}\right)+\frac{17}{7}\)
= \(-\frac{35}{27}+\frac{47}{21}\)
= \(\frac{178}{189}\)
c) \(\frac{117}{13}-\left(\frac{2}{5}+\frac{57}{13}\right)\)
= \(\frac{117}{13}-\frac{311}{65}\)
= \(\frac{274}{65}\)
d) \(\frac{2}{3}-0,25:\frac{3}{4}+\frac{5}{8}.4\)
= \(\frac{2}{3}-\frac{1}{4}:\frac{3}{4}+\frac{5}{8}.4\)
= \(\frac{2}{3}-\frac{1}{3}+\frac{5}{2}\)
= \(\frac{1}{3}+\frac{5}{2}\)
= \(\frac{17}{6}\)
bài 2 tìm x biết
a 13/4 + x = 2
b 2x.17/12 = 3/7
c 2x.17/12= 19/7
d 1/2x + 5/6 = -3
a)
13/4+x=2
x=2-13/4
x=-5/4
b)
2x.17/12=3/7
2x =3/7;17/12
2x =36/119
x =36/119 : 2
x =18/119
c)
2x.17/12=19/7
2x =19/7:17/12
2x =228/119
x =228/119;2
x =114/119
d)
1/2x + 5/6=-3
1/2x =-3-5/6
1/2x =-23/6
x =-23/6:1/2
x =-23/3
Giải phương trình
a)(x+6)/2 + 2(x+17)/2 + 5(x-10)/6 = 2x+6
b)(x+1)/4 - (2x-1)/5 + (2x+1)/2 = (27x+10)/20
c)(x-2)3 + (x-4)3 + (x-7)3 - 3(x-2)(x-4)(x-7) = 0
a)x=-17
b)x=9/10
c)x=4\(\frac{1}{3}\)
tick đi giải chi tiết cho
a)Sử dụng tính chất tỉ lệ thức, có thể biến đổi phương trình như sau
7x+35/3=2x+6/1=>(7x+35)1=3(2x+6)
=>x=-17
b)Sử dụng tính chất tỉ lệ thức, có thể biến đổi phương trình như sau
17x+19/20=27x+10/20=>(17x+19)20=20(27x+10)
c)<=>(x-2)^3+(x-4)^3+(x-7)^3+(-3)(x-2)(x-4)(x-7)=19(3x-13)
=>19(3x-13)=0
rút gọn 57x=247
=>19.3x=19.13
=>3x=13
=>x=13/3
=>x=4\(\frac{1}{3}\)
b)
\(\frac{x+1}{4}-\frac{2x-1}{5}+\frac{2x+1}{2}=\frac{27x+10}{20}\)
<=> \(\frac{5\left(x+1\right)}{20}-\frac{4\left(2x-1\right)}{20}+\frac{10\left(2x+1\right)}{20}=\frac{27x+10}{20}\)
<=> \(5\left(x+1\right)-4\left(2x-1\right)+10\left(2x+1\right)=27x+10\)
<=> \(5x+5-8x+4+20x+10=27x+10\)(Bước này có thể bỏ)
<=> \(10x=-9\)
<=> \(x=-\frac{9}{10}\)
Vậy tập nghiệm của phương trình: S=\(\left(-\frac{9}{10}\right)\) ( thay ngoặc tròn thành ngoặc nhọn )
P/s: Tớ chỉ biết làm như thế thôi!! :)))
Tìm x, biết :
a) 4x(x-5)-(x-1)(1x-3)=23
b) (x-5)(x-4)-(x+1)(x-2)=7
a) `4x(x-5)-(x-1)(x-3)=23`
`<=> 4x^2-20x-x^2+4x-3=23`
`<=>3x^2-16x-26=0`
`<=> x=(8+-\sqrt142)/3
*Nếu đề là: `4x(x-5)-(x-1)(4x-3)=23`
`<=> 4x^2-20x-4x^2+7x-3=23`
`<=>-13x=26`
`<=>x=-2`
b) `(x-5)(x-4)-(x+1)(x-2)=7`
`<=>x^2-9x+20-x^2+x+2=7`
`<=>-8x=-15`
`<=>x=15/8`
\(\text{a) 4x(x-5)-(x-1)(1x-3)=23}\)
\(\Leftrightarrow4x^2-20x-\left(x^2-3x-x+3\right)=23\)
\(\Leftrightarrow4x^2-20x-x^2+3x+x-3=23\)
\(\Leftrightarrow3x^2-16x-26=0\)
Giải phương trình bậc 2 một ẩn ta được :
\(x_1=\dfrac{8-\sqrt{142}}{3};x_2=\dfrac{8+\sqrt{142}}{3}\)
Tìm x:
a) |x|-3/4=5/3
b) |2x-1/3|+5/6=1
c) 17/2-|2x-3/4|=-7/4
d) |2x-1|=(-4) mũ 2
d) khó nhất mk làm nhé :
\(\left|2x-1\right|=\left(-4\right)^2\)
\(\left|2x-1\right|=16\)
\(\Leftrightarrow\orbr{\begin{cases}2x-1=16\\2x-1=-16\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}2x=17\\2x=-15\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=\frac{17}{2}\\x=-\frac{15}{2}\end{cases}}\)