7x-18+9x=4x+54+24
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a: \(\Leftrightarrow x^2\left(9x^2-4\right)=0\)
\(\Leftrightarrow x^2\left(3x-2\right)\left(3x+2\right)=0\)
hay \(x\in\left\{0;\dfrac{2}{3};-\dfrac{2}{3}\right\}\)
b: \(\Leftrightarrow2x^4-4x^2+3x^2-6=0\)
\(\Leftrightarrow x^2-2=0\)
hay \(x\in\left\{\sqrt{2};-\sqrt{2}\right\}\)
d: \(\Leftrightarrow x^4-9x^2+6x^2-54=0\)
\(\Leftrightarrow x^2-9=0\)
=>x=3 hoặc x=-3
18 - 4\(x\) = -20 - 6\(x\)
-4\(x\) + 6\(x\) = - 20 - 18
2\(x\) = - 38
\(x\) = - 19
h, -15 \(\times\) 24 = -7\(x\) + 32
7\(x\) = 360 + 32
7\(x\) = 392
\(x\) = 392:7
\(x\) = 56
i, 15\(x\) -3.(4\(x\) - 6) = -12 + 36
15\(x\) - 12\(x\) + 18 = 24
3\(x\) = 24 - 18
3\(x\) = 6
\(x\) = 2
k, -10\(x\) - 27 = -7\(x\) + 33
-27 - 33 = -7\(x\) + 10\(x\)
3\(x\) = -60
\(x\) = -20
a: Ta có: \(\sqrt{9x-54}-\sqrt{4x-24}=2\)
\(\Leftrightarrow3\sqrt{x-6}-2\sqrt{x-6}=2\)
\(\Leftrightarrow x-6=4\)
hay x=10
b: Ta có: \(\sqrt{4x^2+4x+1}=7\)
\(\Leftrightarrow\left|2x+1\right|=7\)
\(\Leftrightarrow\left[{}\begin{matrix}2x+1=7\\2x+1=-7\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x=6\\2x=-8\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-4\end{matrix}\right.\)
18x -19 = 21 + 8x
18 x - 8x = 21 + 19
10 x = 40
x =4
g) 18 -4x=-20-6x
-4x + 6x = -20 - 18
2x = -38
x= -19
k, -10 \(x\) - 27 = -7\(x\) + 33
-27 - 33 = -7\(x\) + 10\(x\)
3\(x\) = -60
\(x\) - 20
m, -17\(x\) - 24 = -9\(x\) - 40
-24 + 40 = -9\(x\) + 17\(x\)
8\(x\) = 16
\(x\) = 2
\(\dfrac{1}{9x-18}+\dfrac{16-7x}{72-18x}+\dfrac{5}{12x+24}\)
=\(\dfrac{\left(72-18x\right)\left(12x+24\right)}{\left(9x-18\right)\left(72-18x\right)\left(12x+24\right)}+\dfrac{\left(16-7x\right)\left(9x-18\right)\left(12x+24\right)}{\left(72-18x\right)\left(9x-18\right)\left(12x+24\right)}+\dfrac{5\left(9x-18\right)\left(72-18x\right)}{\left(12x+24\right)\left(9x-18\right)\left(72-18x\right)}\)
=\(\dfrac{\left(72-18x\right)\left(12x+24\right)+\left(16-7x\right)\left(9x-18\right)\left(12x+24\right)+5\left(9x-18\right)\left(72-18x\right)}{\left(9x-18\right)\left(72-18x\right)\left(12x+24\right)}\)
=\(\dfrac{-756x^3+702x^2+8316x-11664}{\left(9x-18\right)\left(72-18x\right)\left(12x+24\right)}\)
=
Ngô thừa ân cái đề nhìn rối quá bạn ơi , có thể viết rõ ra hơn được không !
e, \(18x-19=21+8x\)
\(\Rightarrow18x-8x=21+19\)
\(\Rightarrow10x=30\)
\(\Rightarrow x=3\)
Vậy \(x=3\)
g, \(18-4x=-20-6x\)
\(\Rightarrow-4x+6x=-20-18\)
\(\Rightarrow-2x=-38\)
\(\Rightarrow x=19\)
Vậy \(x=19\)
h, \(-15x-24=-7x-32\)
\(\Rightarrow-15x+7x=-32+24\)
\(\Rightarrow-8x=-8\)
\(\Rightarrow x=1\)
Vậy \(x=1\)
i, \(15x-3\left(4x-6\right)=-12+36\)
\(\Rightarrow15x-12x+18=-12+36\)
\(\Rightarrow7x=-12+36-18\)
\(\Rightarrow7x=6\)
\(\Rightarrow x=\frac{6}{7}\)
Vậy \(x=\frac{6}{7}\)
k, \(-10x-27=-7x+33\)
\(\Rightarrow-10x+7x=33+27\)
\(\Rightarrow-3x=60\)
\(\Rightarrow x=-20\)
m, \(-17x-24=-9x-40\)
\(\Rightarrow-17x+9x=-40+24\)
\(\Rightarrow-8x=-16\)
\(\Rightarrow x=2\)
Vậy \(x=2\)
n, \(-23x-25=-18x+75\)
\(\Rightarrow-23x+18x=75+25\)
\(\Rightarrow-5x=100\)
\(\Rightarrow x=-20\)
Vậy \(x=-20\)
p, \(-5x+7\left(2x-3\right)=4\left(x-4\right)\)
\(\Rightarrow-5x+14x-21=4x-16\)
\(\Rightarrow-5x+14x-4x=-16+21\)
\(\Rightarrow5x=5\)
\(\Rightarrow x=1\)
Vậy \(x=1\)
q, \(24-6\left(3x+1\right)=-5\left(4x-4\right)-8\)
\(\Rightarrow24-18x-6=-20x+20-8\)
\(\Rightarrow-18x+20x=20-8-24+6\)
\(\Rightarrow2x=-6\)
\(\Rightarrow x=-3\)
Vậy \(x=-3\)
r, \(18-4\left(6-2x\right)=-3\left(4x+5\right)-11\)
\(\Rightarrow18-24+8x=-12x-15-11\)
\(\Rightarrow8x+12x=-15-11-18+24\)
\(\Rightarrow20x=-20\)
\(\Rightarrow x=-1\)
Vậy \(x=-1\)
s, \(-5\left(4x-5\right)-14=6\left(2-3x\right)-10x-9\)
\(\Rightarrow-20x+25-14=12-18x-10x-9\)
\(\Rightarrow-20x+18x+10x=12-9+14-25\)
\(\Rightarrow8x=-8\)
\(\Rightarrow x=-1\)
Vậy \(x=-1\)
Chúc bạn hok tốt!!! tỷ tỷ
\(4x^3-13x^2+9x-18=4x^3-12x^2-x^2+3x+6x-18\)
\(=4x^2.\left(x-3\right)-x\left(x-3\right)+3.\left(x-3\right)=\left(x-3\right)\left(4x^2-x+3\right)\)
\(4x^3-13x^2+9x-18\)
\(=4x^3-12x^2-x^2+3x+6x-18\)
\(=4x^2\left(x-3\right)-x\left(x-3\right)+6\left(x-3\right)\)
\(=\left(x-3\right)\left(4x^2-x+6\right)\)
7x-18+9x=4x+54+24
7x+9x=4x+78+18
7x+9x=4x+96
16x-4x=96
12x=96
x=96:12
x=8
7x-18+9x=4x+78
7x+9x=4x+78+18
7x+9x=4x+96
16x-4x=96
12x=96
x=96:12
x=8