Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
-2.(\(x\) + 6) + 5.(3 - 2\(x\)) = 87
-2\(x\) - 12 + 15 - 10\(x\) = 87
-(2\(x\) + 10\(x\)) + (15 - 12) = 87
-12\(x\) + 3 = 87
3 - 87 = 12\(x\)
12\(x\) = -84
\(x\) = -84 : 12
\(x\) = -7
Sai đề :
2 x 53 x 12 + 4 x 6 x 87 - 3 x 8 x 40
= 12 x 2 x 53 + 4 x 6 x 87 - 3 x 8 x 40
= 24 x 53 + 24 x 87 - 24 x 40
= 24 x ( 53 + 87 - 40 )
= 24 x ( 140 - 40 )
= 24 x 100
= 2400
Sai đề :
2 x 53 x 12 + 4 x 6 x 87 - 3 x 8 x 40
= 12 x 2 x 53 + 4 x 6 x 87 - 3 x 8 x 40
= 24 x 53 + 24 x 87 - 24 x 40
= 24 x ( 53 + 87 - 40 )
= 24 x ( 140 - 40 )
= 24 x 100
= 2400
a) 125-(199-x )=72
125 - ( 199-x) = 49
199-x = 76
x = 123
b) 12.(x-3):3=42-23
12(x-3) :3 = 16 - 8
12(x-3) : 3 = 8
12(x-3) = 24
x-3 = 2
x = 5
c) 6+3x+2=87
3x+2 = 81
3x+2 = 34
x + 2 = 4
x= 2
a) 199-x=76
x=123
b) 12.(x-3):3=8
12.(x-3)=24
x-3 =2
x =5
c) 3x.32 = 81
3x=9
=> x =2
a, \(\left(x+1\right)^3:\left(x+1\right)=4\)
\(\Leftrightarrow\left(x+1\right)^2=4\)
\(\Leftrightarrow\left(x+1\right)^2=2^2\)
\(\Leftrightarrow\left[{}\begin{matrix}x+1=2\\x+1=-2\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1\\x=-3\end{matrix}\right.\)
Vậy .....
b, \(3^x+60=87\)
\(\Leftrightarrow3^x=87-60\)
\(\Leftrightarrow3^x=27\)
\(\Leftrightarrow3^x=3^3\)
\(\Leftrightarrow x=3\)
Vậy ...
c, (Viết cái đề khó nhìn quá à)
d, \(2^x-64=2^6\)
\(\Leftrightarrow2^x-64=64\)
\(\Leftrightarrow2^x=64+64\)
\(\Leftrightarrow2^x=128\)
\(\Leftrightarrow2^x=2^7\)
\(\Leftrightarrow x=7\)
Vậy ...
2: \(=\dfrac{-2}{75}+\dfrac{5}{39}=\dfrac{33}{325}\)
3: \(=\dfrac{6}{11}\left(\dfrac{4}{9}+\dfrac{5}{9}\right)=\dfrac{6}{11}\)
4: \(=\dfrac{7}{19}\left(\dfrac{5}{13}+\dfrac{8}{13}-1\right)=-2\cdot\dfrac{7}{19}=-\dfrac{14}{19}\)
5: \(=\dfrac{2}{7}\left(\dfrac{4}{23}-\dfrac{27}{23}+1\right)=0\)
6: \(=\dfrac{3}{8}\left(\dfrac{3}{7}+\dfrac{4}{7}\right)+\dfrac{11}{8}=\dfrac{3}{8}+\dfrac{11}{8}=\dfrac{14}{8}=\dfrac{7}{4}\)
6 + 3x+2 = 87
=> 3x+2 = 81
=> 3x+2 = 34
=> x + 2 = 4
=> x = 2
\(6+3^{x+2}=87\)
\(\Rightarrow3^{x+2}=87-6\)
\(\Rightarrow3^{x+2}=81=3^4\)
\(\Rightarrow x+2=4\)
\(\Rightarrow x=4-2=2\)