4+6
5+7
1+9
7+8
1,
a, 20,2 x 5,1 - 30,3 x 3,4 + 14,58
14,58 x 460 + 7,29 + 540 x 2
b, 1/1000 + 13/1000 + 25/1000 + ...+ 97/1000 + 109/1000
2,
a, 6/8 = 15/x
b, (x+1) + (x + 4) + (x + 7) + ... + (x + 28) - 155
c, 71 + 65 x 4 = y + 140/y +260
a.1 là phân số nhé. Các bạn giúp mình với mình đang cần gấp
\(\frac{x-2}{71}+\frac{x-4}{69}=\frac{x-6}{67}+\frac{x-8}{65}\)
giải hộ tớ vơi. mai tớ ktra rồi
\(\frac{x-2}{71}+\frac{x-4}{69}=\frac{x-6}{67}+\frac{x-8}{65}\)
\(\Leftrightarrow\frac{x-2}{71}-1+\frac{x-4}{69}-1=\frac{x-6}{67}-1+\frac{x-8}{65}-1\)
\(\Leftrightarrow\frac{x-73}{71}+\frac{x-73}{69}=\frac{x-73}{67}+\frac{x-73}{65}\)
\(\Leftrightarrow\frac{x-73}{71}+\frac{x-73}{69}-\frac{x-73}{67}-\frac{x-73}{65}=0\)
\(\Leftrightarrow\left(x-73\right)\left(\frac{1}{71}+\frac{1}{69}-\frac{1}{67}-\frac{1}{65}\right)=0\)
Mà \(\frac{1}{71}+\frac{1}{69}-\frac{1}{67}-\frac{1}{65}\ne0\)
\(x-73=0\Leftrightarrow x=73\)
\(\frac{x-2}{71}-1+\frac{x-4}{69}-1=\frac{x-6}{67}-1+\frac{x-8}{65}-1\)
\(\Leftrightarrow\frac{x-73}{71}+\frac{x-73}{69}=\frac{x-73}{67}+\frac{x-73}{65}\)
\(\Leftrightarrow\left(x-3\right)\left(\frac{1}{71}+\frac{1}{69}-\frac{1}{67}-\frac{1}{65}\right)=0\)
\(\Rightarrow...\)
Ta có: \(\frac{x-2}{71}+\frac{x-4}{69}=\frac{x-6}{67}+\frac{x-8}{65}\)
\(\frac{x-2}{71}+\frac{x-4}{69}-2=\frac{x-6}{67}+\frac{x-8}{65}\)
\(\frac{x-2}{71}-1+\frac{x-4}{69}-1=\frac{x-6}{67}-1+\frac{x-8}{65}-1=0\)
\(\frac{x-73}{71}+\frac{x-73}{69}-\frac{x-6}{67}-\frac{x-8}{65}=0\)
\(\left(x-73\right)\left(\frac{1}{71}+\frac{1}{69}-\frac{1}{67}-\frac{1}{65}\right)=0\)
\(\left(\frac{1}{71}+\frac{1}{69}-\frac{1}{67}-\frac{1}{65}\right)\ne0\)
=> x - 73 = 0 <=> x = 73
Vậy x = 73.
71+65*4 =y+140/y+260
71+65×4=(x+140)÷x+260
71+65 x 4=x+140/x+260
71 + 65 x 4 = x + 140/x + 260
\(\frac{x+140}{x}\)phân tích ra thành \(\frac{x}{x}+\frac{140}{x}\)đó Ngọc Nguyễn Minh
71 + 65 x 4 = x + 140 / x + 260.
x=400x331
x=132400
tích nha!mk tích bn rùi đó
71+260=x/(140+260)
331=x/400
x=400x331=132400
71 + 65 x 4 = x +140 :x + 260
331=x+140:x+260
331=x: [140+260]
331=x:400
x=331 nhân 400
x=132 400
hok tốt
x = 2
* Cách giải lên lớp 6 học *
\(71+65\times4=\frac{x+140}{x}+260\)
\(\Leftrightarrow331=\frac{x+140}{x}+260\)
\(\Leftrightarrow71=\frac{x+140}{x}\)
\(\Leftrightarrow x+140=71.x\)
\(\Leftrightarrow140=71.x-x\)
\(\Leftrightarrow140=x\left(71-1\right)\)
\(\Leftrightarrow140=x70\)
\(\Leftrightarrow x=140:70=2\)
Tim x
1) x - 26 = 95 2) 79 - x = 65 3) 119 - x = 97
4) (x - 67) - 23 = 10 5) ( x - 97 ) - 68 = 35 6) 135 - (x + 43) = 67
7) 289 - (x+167) = 65 8) 167 - ( x - 33 ) = 133 9) 465 - (x - 57) = 364
1)x - 26 =95 2)79 - x = 65 3)119 - x =97 4) (x - 67) -23 =10
x =95+26 x=79-65 x =119-97 x - 67 =10+23 =33
x =121 x=14 x =22 x =33+67
x =100
71+65 nhân 4 =x+140/x+260