X x 3/8 = 4 nhanh nha
3/15- x = -1/7
[4,5 + 3/4.x] : 8/3 =9/8
[x-1/4] . 3/28+ 2 và 7/9 = 8 và 7/9
/ là phần nha làm nhanh có quà
a, \(\dfrac{3}{15}-x=-\dfrac{1}{7}\Leftrightarrow\dfrac{21-105x}{105}=\dfrac{-15}{105}\Rightarrow-105x=-36\)
\(\Leftrightarrow x=\dfrac{36}{105}=\dfrac{12}{35}\)
b, \(\left(4,5+\dfrac{3}{4}x\right):\dfrac{8}{3}=\dfrac{9}{3}\Leftrightarrow\dfrac{45}{10}+\dfrac{3x}{4}=\dfrac{72}{9}=8\)
\(\Leftrightarrow\dfrac{36}{4}+\dfrac{3x}{4}=\dfrac{32}{4}\Rightarrow3x=-4\Leftrightarrow x=-\dfrac{4}{3}\)
c, mình ko hiểu đề lắm
Tính nhanh :
27 x 8 x 3
=
6 x 4 x 18 gạch ở giữa nha C.ơn
\(\dfrac{27\cdot8\cdot3}{6\cdot4\cdot18}=\dfrac{27}{18}\cdot\dfrac{3}{6}\cdot\dfrac{8}{4}=\dfrac{27}{18}=\dfrac{3}{2}\)
\(=\dfrac{3\times2}{2\times2}=\dfrac{3}{2}\)
-2.(2.x-8)+3.(4-2.x)=-72-5.(3.x-7)
giúp mik nha mik cần nhanh nha
-2(2.x-8)+3(4-2.x)=-72-5(3.x-7)
<=>16-4x+12-6x =-72-15x+35
<=>16-4x+12-6x+72+15x-35=0
<=>65+5x=0
<=>x=-13
Nhớ tick cho mk hen😀
[x+2]+[x+4]+[x+6]+...+[x+20]=160
[1/2+1/4+1/8+...+1/64]/x=3/8
làm giúp mình nha ai nhanh thì tick
\(\left(x+2\right)+\left(x+4\right)+...+\left(x+20\right)=160\)
\(x+2+x+4+...+x+20=160\)
\(\left(x+x+x+...+x\right)+\left(2+4+...+20\right)=160\)
\(x\cdot20+\frac{\left(20+2\right)\cdot\left(\left(20-2\right):2+1\right)}{2}=160\)
\(x\cdot20+110=160\)
\(x\cdot20=160-110\)
\(x\cdot20=50\)
\(x=50:20\)
\(x=2,5\)
Vậy \(x=2,5\)
[ x + 2 ] + [ x + 4 ] + [ x + 6 ] + ... + [ x + 20 ] = 160
( 20 + 2 ) x 10 : 2 + 10x = 160
22 x 10 : 2 + 10x = 160
220 : 2 + 10x = 160
110 + 10x = 160
10x = 160 - 110
10x = 50 ; x = 5
[ 1/2 + 1/4 + 1/8 + ... + 1.64 ] /x = 3/8
=> [ ( 1/2 + 1/4 ) + ( 1/8 + 1/16 ) + ( 1/32 + 1/64 ) ] / x = 3/8
[ 3/4 + 3/16 + 3/64 ] / x = 3/8
[ 48/64 + 12/64 + 3/64 ] / x = 3/8
=> 63/64x = 3/8
=> 64x = 21 x 8
64x = 168
x = 2,625
k chắc nha
Tìm x:
2 (x-5) -3 (x+7)=14
-(-3-x+8)-(-3+5)=|15-8|
-5-8(4-x+5)=4+3+9
45-(x+45-3)=|-7+3|
Trả lời rõ ràng nha, nếu nhanh tay mk tick nhá
2(x-5)-3(x+7)=14
=> 2x-10-3x-21=14
=> x(2-3)-31=14
=> -x=14+31
=> -x=45
=> x=-45
2 x 3 x 4 x 8 50 x 25 x 125
tính nhanh đó nha
\(2x3x4x8x50x25x125=\left(2x50\right)x\left(4x25\right)x\left(8x125\right)x3\)\(=100x100x1000x3=30000000\)
10 : 2 x 5 + 3 - 7 x 8 x 4 = ?
ai nhanh nhất thì sẽ đc tick nha
10 : 2 x 5 + 3 - 7 x 8 x 4 = ?
ai nhanh nhất thì sẽ đc tick nha
B=3/4 x 8/9 x15/16 x ..... x 120/121
Trả lời nhanh giùm mình nha
B=1x3/2x2x2x4/3x3x3x5/4x4x...x10x12/11x11
B=1x3x2x4x3x5x...x10x12/2x2x3x3x4x4x...x11x11
B=(1x2x3x...x10)x(2x3x5x...x12)/(2x3x4x...x11)x(2x3x4x...x11)
B=1x12/11x2
B=12/22
B=6/11
Vậy B = 6/11