tìm x:
3x+2+3x+1+34=405
Những câu hỏi liên quan
Tìm x, biết:
2 . 3x - 405 = 3x-1
\(2\cdot3^x-405=3^{x-1}\\\Rightarrow2\cdot3^x-3^{x-1}=405\\\Rightarrow2\cdot3^x-3^x\cdot3^{-1}=405\\\Rightarrow3^x\cdot(2-3^{-1})=405\\\Rightarrow3^x\cdot(2-\frac13)=405\\\Rightarrow3^x\cdot\frac53=405\\\Rightarrow3^x=405:\frac53\\\Rightarrow3^x=243\\\Rightarrow3^x=3^5\\\Rightarrow x=5\)
Đúng 3
Bình luận (0)
tìm x, biết:
a. 2 . 3x - 405 = 3^x - 1
b.(1/81)^x . 27^2x = (-9)^4
Tìm x, biết:
\(\left(3x+1\right)^2+\left(5x-2\right)^2=34\left(x+2\right)\left(x-2\right)\)
\(3x\left(x-4\right)-x\left(5+3x\right)=-34\)
tìm x thuộc Z
-2(-34-7x)+5c(-3x-14)=2
-13(-7+3x)-(-985+91)=20(-34-x)-6(3x-16)
Tìm x
a) x (3x - 2) - 3x (x + 5) = - 34
b) (2x + 3) . (3x - 2) - 6x . (x - \(\frac{1}{2}\)) = 26
a) x (3x - 2) - 3x (x + 5) = - 34
<=> 3x2-2x-3x2-15x=-34
<=>-17x=-34
<=>x=\(\frac{-34}{-17}\)
<=>x=2
b) (2x + 3) . (3x - 2) - 6x . (x - \(\frac{1}{2}\) ) = 26
<=>6x2-4x+9x-6-6x2 +3x=26
<=>8x=26+6=32
<=>x=32:8=4
nếu đúng nhớ k cho mk và kết bn nha!mk trả lời nhanh nhất đó. thank. chúc bn học tốt!
Đúng 0
Bình luận (0)
a) \(\Leftrightarrow x=2\)
b) \(\Leftrightarrow x=32\div8=4\)
Hk tốt
Đúng 0
Bình luận (0)
a)\(x\left(3x-2\right)-3x\left(x+5\right)=-34\)
\(\Leftrightarrow3x^2-2x-3x^2-15x=-34\)
\(\Leftrightarrow15x-2x=-34\)
\(\Leftrightarrow13x=-34\)
\(\Leftrightarrow x=\frac{-34}{13}\)
b) \(\left(2x+3\right)\left(3x-2\right)-6x\left(x-\frac{1}{2}\right)=26\)
\(\Leftrightarrow6x^2+5x-6-6x^2+3x=26\)
\(\Leftrightarrow8x-6=26\)
\(\Leftrightarrow8x=26+6\)
\(\Leftrightarrow8x=32\)
\(\Leftrightarrow x=32\div8\)
\(\Leftrightarrow x=4\)
Vậy \(x=4\)
Đúng 0
Bình luận (0)
tìm x
1. 3x - 7 = 19
2. (2x+1) . (x-3)=0
3. 3x+2/4 +1=5x-1/3
4. x/15 + 1/2 - x/50 = 5/6
5. x4 - 2x3 + 3x2 - 2x + 1=0
\(1,3x-7=19\\ \Rightarrow3x=26\\ \Rightarrow x=\dfrac{26}{3}\\ 2,\left(2x+1\right)\left(x-3\right)=0\\ \Rightarrow\left[{}\begin{matrix}2x+1=0\\x-3=0\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=-\dfrac{1}{2}\\x=3\end{matrix}\right.\\ 3,3x+\dfrac{2}{4}+1=5x-\dfrac{1}{3}\\ \Rightarrow5x-\dfrac{1}{3}-3x-\dfrac{2}{4}-1=0\\ \Rightarrow2x-\dfrac{11}{6}=0\\ \Rightarrow2x=\dfrac{11}{6}\\ \Rightarrow x=\dfrac{11}{12}\)
\(4,\dfrac{x}{15}+\dfrac{1}{2}-\dfrac{x}{50}=\dfrac{5}{6}\\ \Rightarrow\dfrac{x}{15}-\dfrac{x}{50}=\dfrac{5}{6}-\dfrac{1}{2}\\ \Rightarrow x\left(\dfrac{1}{15}-\dfrac{1}{50}\right)=\dfrac{1}{3}\\ \Rightarrow\dfrac{7}{150}x=\dfrac{1}{3}\\ \Rightarrow x=\dfrac{50}{7}\)
Đúng 0
Bình luận (0)
B1
a)2-3x/x-2=-7/5
b)2x3x-405=3x-1
c)x-1/2=y-2/5=z-3/4 và 2x+3y-z=50
d3x=y,5y=4z và 6x+7y+8z=456
a: \(\Leftrightarrow-15x+10=-7x+14\)
=>-8x=4
hay x=-1/2
Đúng 0
Bình luận (0)
\(a,\dfrac{2-3x}{x-2}=-\dfrac{7}{5}\left(x\ne2\right)\\ \Leftrightarrow14-7x=10-15x\\ \Leftrightarrow8x=-4\Leftrightarrow x=-2\left(tm\right)\\ c,\Leftrightarrow\dfrac{x-1}{2}=\dfrac{y-2}{5}=\dfrac{z-3}{4}=\dfrac{2x-2+3y-6-z+3}{2\cdot2+5\cdot3-4}=\dfrac{45}{15}=3\\ \Leftrightarrow\left\{{}\begin{matrix}x-1=6\\y-2=15\\z-3=12\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=7\\y=17\\z=15\end{matrix}\right.\\ d,\Leftrightarrow\dfrac{x}{1}=\dfrac{y}{3};\dfrac{y}{4}=\dfrac{z}{5}\\ \Leftrightarrow\dfrac{x}{4}=\dfrac{y}{12}=\dfrac{z}{15}=\dfrac{6x+7y+8z}{24+84+120}=\dfrac{456}{228}=2\\ \Leftrightarrow\left\{{}\begin{matrix}x=8\\y=24\\z=30\end{matrix}\right.\)
Đúng 0
Bình luận (0)
Tìm x, biếta)
x
:
−
2
1
15
+
3
1
2
−
3
4
b)
−
5
8
−
x
:
3
5
6
+
7
3
4
−
2
c)
x
−...
Đọc tiếp
Tìm x, biết
a) x : − 2 1 15 + 3 1 2 = − 3 4 b) − 5 8 − x : 3 5 6 + 7 3 4 = − 2
c) x − 3 4 − 1 4 = 0 d) 3 4 : 2 4 9 − − 3 x + 2 2 3 = 3 4
e) x − 1 3 = 2 − 3 x f) 3 5 7 x − 1 5 7 x − 1 3 = 2 3
g) − 3 4 3 x − 1 = − 27 64 h) 4 5 2 x + 5 = 256 625
i) x − 2 15 3 = 8 125 k) x + 3 5 x + 3 2 = 64 27
m) x − 1 x + 5 = 6 7 n) 4 13 . 6 5 + 4 13 . 2 5 . 2 x + 1 2 = 10 13
3^2x-1+2.9x-1=405
3/5.(3x^3-8/9)-1/2.(3/2-1)=-1/4
\(\left(\dfrac{1}{3}\right)^{x-1}+5.\left(\dfrac{1}{3}\right)^{x+1}=\dfrac{14}{9^3}\)
tìm x ( giúp với mình cần gấp )
(3x-1)/(40-5x)=(25-3x)/(5x-34)
Tìm x