Tim y:
(6400+4600)-7y=3839
Tim y:
a)219-7(y+1)=100
b)(3y-6).3=3^4
c)(4600+6400)-7y=3839
d)[(8y-14):2-2]-31=341
TRen 11 kb vs mk nha
a) 219 - 7(y + 1) = 100
=> 7(y + 1) = 119
=> y + 1 = 19
=> y = 18
vậy_
a) 219 - 7(y+1) = 100
7(y+1) = 119
y+1 = 17
y = 16
các bài cn lại lm tương tự nha!
a, 219-7(y+1)=100
7(y+1)=219-100
7(y+1)=119
y+1=119:7
y+1=17
y=17-1
y=16
Tìm x biết : (4600+6400)-7x=3839
( 4600 + 6400 ) - 7x = 3839
11000 - 7 . x = 3839
7 . x = 11000 - 3839
7 . x = 7161
x = 7161 : 7
x = 1023
Vậy x = 1023
x = 1023 nhé câu này mình lm rồi
20-[7(x-3)+4]=2
(4600+6400)-7x=3839
tìm x
a)(4600 + 6400) - 7.x = 3839
b)[(8x - 14 ) : 2 - 2 ]. 31 = 341
c)2.(x - 3) - x = 4.23
a) (4600 + 6400) -7.x=3839
11000 - 7.x=3839
7.x=11000-3839
7.x=7161
x=7161:7
x=1023
b) (8x-14) :2-2= 341:31
(8x-14):2-2=11
(8x-14):2= 11+2
(8x-14):2=13
8x-14=13.2
8x-14=26
8x=26+14
8x=40
x=40:8
x=5
a) \(\left(4600+6400\right)-7x=3839\Rightarrow11000-7x=3839\)
\(\Rightarrow-7x=3839-11000\)
\(\Rightarrow7x=7161\Rightarrow x=1023\)
tìm x
a)(4600 + 6400) - 7.x = 3839
b)[(8x - 14 ) : 2 - 2 ]. 31 = 341
c)2.(x - 3) - x = 4.23
a)(4600 + 6400) - 7.x = 3839
11000-7x=3839
7x=7161
x=1023
Vậy x=1023
b)[(8x - 14 ) : 2 - 2 ]. 31 = 341
(8x - 14 ) : 2 - 2=11
(8x - 14 ) : 2=13
8x - 14 =26
8x=40
x=5
Vậy x=5
c)2.(x - 3) - x = 4.2^3
2.(x - 3) - x=32
2x-6-x=32
x-6=32
x=38
Vậy x=38
Bài 1 : Tìm x
a, ( 4600 + 6400 ) - 7.x = 3839
11000 - 7.x = 3839
7.x = 11000 - 3839
7.x = 7161
x = 7161: 7
x = 1023
b, [ ( 8x - 14 ) : 2 - 2 ] . 31 = 341
( 8x -14 ) : 2 -2 = 11
( 8x -14 ) : 2 = 13
8x -14 = 26
8x = 40
x = 5
c, 2. ( x -3 ) - x = 4. 23
2x - 6 - x = 32
x - 6 = 32
x = 38
6400+4600=?
Tổng là:
6400+4600=11000
Đáp số : 11000
Tim x ; y biet: (5x-1)/3 = (7y-6)/5 = (5x-7y-7)/4x
Tim x y bt x+y=30 & 6x+7y=180
tim x;y
\(\frac{5x-1}{3}=\frac{7y-6}{5}=\frac{5x+7y-7}{4x}\)
Từ \(\frac{5x-1}{3}=\frac{7y-6}{5}\) Áp dụng TC DTSBN ta có :
\(\frac{5x-1}{3}=\frac{7y-6}{5}=\frac{\left(5x-1\right)+\left(7y-6\right)}{3+5}=\frac{5x+7y-7}{8}=\frac{5x+7y-7}{4x}\)
\(\Rightarrow4x=8\Rightarrow x=2\)
\(\Rightarrow\frac{5.2-1}{3}=\frac{7y-6}{5}\)
\(\Leftrightarrow\frac{7y-6}{5}=3\)
\(\Rightarrow y=3\)
Vậy \(x=2;y=3\)
\(\frac{5x-1}{3}=\frac{7y-6}{5}\Rightarrow5\left(5x-1\right)=3\left(7y-6\right)\Rightarrow25x-5=21y-18\)
\(\Rightarrow21y=25x+13\Rightarrow7y=\frac{25x+13}{3}\)
Xét : \(\frac{5x+7y-7}{4x}=\frac{5x+\frac{25x+13}{3}-7}{4x}=\frac{10x-2}{3x}\)
\(\Rightarrow3x\left(5x-1\right)=3\left(10x-2\right)\Rightarrow15x^2-33x+6=0\)
\(\Rightarrow3\left(x-2\right)\left(5x-1\right)=0\Rightarrow\orbr{\begin{cases}x=2\\x=\frac{1}{5}\end{cases}}\)
Với x=2 , ta có : y=3
Với x =\(\frac{1}{5}\), ta có : y= \(\frac{6}{7}\)