tìm x
x*2+x*3=4
x*9-1,5=30
`x xx2+x xx3=4`
`x xx(2+3)=4`
`x xx5=4`
`x=4:5=4/5`
_______________________
`x xx9-1,5=30`
`x xx9=30+1,5`
`x xx 9=31,5`
`x=31,5:9`
`x=3,5`
\(x\times2+x\times3=4\)
\(x\times\left(2+3\right)=4\)
\(x\times5=4\)
\(x=4:5\)
\(x=\dfrac{4}{5}\)
\(x\times9-1,5=30\)
\(x\times9=30+1,5\)
\(x\times9=31,5\)
\(x=31,5:9\)
\(x=3,5\)
a,X x 2 + X x 3=4
X x(2+3) =4
X x 5 =4
X 4/5
b, 9xX-1,5=30
9xX =30+1,5=31,5
X = 31,5:9
X =3,5
a)x*2+x*3=4 b)x*9-1,5=30
các bạn giúp mình với,mình cần gấp
a) x*2+x*3=4
x*(2+3)=4
x*5=4
x=4:5
x=4/5(0,8)
Vậy x = 4/5 (0,8)
b)x*9-1,5=30
x*9 = 30+1,5
x*9 = 31,5
x = 31,5 : 9
x = 3,5
Vậy x = 3,5
a) X x 2 + X x 3 = 4 b) X x 9 - 1,5 = 30
X x ( 2 + 3 ) = 4 X x 9 = 30 + 1,5
X x 5 = 4 X x 9 = 31,5
X = 4 : 5 X = 31,5 : 9
X = 0,8 X = 3,5
~ Hok T ~
Tìm x:
a, x/1,5 = 4/3
b, 2/9 = x/ -72
c, x : -3/8 = 1/3
\(\frac{x}{1,5}=\frac{4}{3}\Rightarrow x=\frac{4.1,5}{3}=2\)
\(\frac{2}{9}=\frac{x}{-72}\Rightarrow x=\frac{2.\left(-72\right)}{9}=-16\)
\(x:-\frac{3}{8}=\frac{1}{3}\)
\(x=\frac{1}{3}.\left(-\frac{3}{8}\right)\)
\(x=-\frac{1}{8}\)
tick cho mk nha:
a) \(\frac{x}{1,5}=\frac{4}{3}\) \(\Rightarrow x=1,5\times4\div3\) =2 .
b) \(\frac{2}{9}=\frac{x}{-72}\) \(\Rightarrow x=-72\times2\div9\) = \(-16\)
c) \(x\div\frac{-3}{8}=\frac{1}{3}\) \(\Rightarrow x=\frac{1}{3}\times\frac{-3}{8}\) \(x=\frac{-1}{8}\)
chúc bn hc tốt nha!
Tìm x a) (x-1/3).(x+2/3)=0 b) (3/4x-9/16).(1,5+(-3):x)=0
\(a,\left(x-\dfrac{1}{3}\right)\left(x+\dfrac{2}{3}\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1}{3}\\x=-\dfrac{2}{3}\end{matrix}\right.\\ b,\left(\dfrac{3}{4}x-\dfrac{9}{16}\right)\left(1,5+\dfrac{-3}{x}\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}\dfrac{3}{4}x=\dfrac{9}{16}\\-\dfrac{3}{x}=-1,5=-\dfrac{3}{2}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{4}\\x=2\end{matrix}\right.\)
a: \(\left(x-\dfrac{1}{3}\right)\left(x+\dfrac{2}{3}\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1}{3}\\x=-\dfrac{2}{3}\end{matrix}\right.\)
b: \(\left(\dfrac{3}{4}x-\dfrac{9}{16}\right)\left(\dfrac{1}{5}+\left(-3\right):x\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}\dfrac{3}{4}x=\dfrac{9}{16}\\\left(-3\right):x=-\dfrac{1}{5}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{9}{16}:\dfrac{3}{4}=\dfrac{9}{16}\cdot\dfrac{4}{3}=\dfrac{3}{4}\\x=\left(-3\right):\dfrac{-1}{5}=15\end{matrix}\right.\)
Bài 1: Tìm x :A) 3/4.(x-2) - 1/2.(6-2.x)= 1/6.x + 5
B) -1/2.(3.x + 5) - 2/3.(9-6.x) = 3/5.(x-10) - 3
C) (1/4.x - 1,5) + (5/6.x - 3) - (5/8.x -0,5) = -4,5
Tìm x : A, ( -x + 3/5 ) + 13/20 = 5/6 B, x - 5/9 = 4/9 C, 3/2 - 2x = 5 1/3 : 8/3 D, ( x + 1,5 ) : 3 1/5 = -5/8 Lưu ý : 5 1/3 và 3 1/5 là hỗn số
a: =>3/5-x+13/20=5/6
=>11/10-x=5/6
=>x=11/10-5/6=4/15
b: =>x=4/9+5/9=1
c: =>3/2-2x=16/3:8/3=2
=>2x=-1/2
=>x=-1/4
d: =>x+1,5=-5/8*8/5=-1
=>x=-2,5
Bài 1 :So sánh
a) 3^28 và 4^21
b) 8^30 và 16^22
c) 2^69 và 3^46
c) 27^20 và 9^31
Bài 2: Tìm x thuộc Q, biết
a) ( x+3/7 )^9=0
b) ( x-1,5 )^6=1
c) ( 3x-5 )^3=-27
d) ( x+1/3 )^2=1/81
Bài 3: Chứng minh rằng:
a) 5^18+5^17-5^16 chia hết cho 29
b) 125^6+5^17-25^8 chia hết cho 29
c) 4^45+8^29 chia hết cho 9
Bài 4: Tìm số tự nhiên x, biết rằng:
a) 3^x+3^x+2=2430
b) 7^x-3+5.7^x-3=294
Tìm x
X×2+x×3=4 x×9-1,5=30
x . 2 + x . 3 = 4
x . ( 2+3 ) = 4
x. 5 = 4
x = 4: 5 = 0,8
x . 9 - 1,5 = 30
x . 9 = 30 + 1.5 = 31.5
x = 31.5 : 9 = 3.5
tìm x thuộc Z
a) -30+ ( 25-x)= -1
b) (x+5) + ( x-9)=x+ 2
c) 30(x+2) - 6(x-5)-24x =100
d) 2(x-5) - 3(x-4)=-6+15.(-3)
a, Ta có :\(-30+\left(25-x\right)=-1\)
\(\Leftrightarrow\left(-30\right)+25-x=-1\)
\(\Leftrightarrow25-x=\left(-1\right)-\left(-30\right)\)
\(\Leftrightarrow25-x=29\\ \Leftrightarrow x=25-29\)
\(\Leftrightarrow x=\left(-4\right)\)
Vậy \(x=-4\)
b,Ta có :\(\left(x+5\right)+\left(x-9\right)=x+2\)
\(\Leftrightarrow x+5+x-9=x+2\)
\(\Leftrightarrow2.x+\left(5-9\right)=x+2\)
\(\Leftrightarrow\) \(2.x+\left(-4\right)=x+2\)
\(\Leftrightarrow2.x-x=4+2\)
\(\Leftrightarrow x=6\)
Vậy \(x=6\)
