(\(x\) \(\times\) (\(x\) + 1)): 2 = 153

(\(x\) \(\times\) (\(x\) + 1)) = 153  \(\times\) 2

\(x\) \(\times\) (\(x\) + 1) = 306

\(x\)² + \(x\) = 306

\(x^2\) + \(x\) - 306 = 0

\(x^2\) - 17\(x\) + 18\(x\) - 306 =0

\(x\) \(\times\) (\(x\) - 17) + 18 \(\times\) (\(x\) - 17) = 0

(\(x\) - 17)\(\times\) ( \(x\) + 18) = 0

\(\left[{}\begin{matrix}x-17=0\\x+18=0\end{matrix}\right.\)

\(\left[{}\begin{matrix}x=17\\x=-18\end{matrix}\right.\)

\(\text{#040911}\)

\(x\cdot\left(x+1\right)\div2=153\)

\(\Rightarrow x\cdot\left(x+1\right)=153\cdot2\)

\(\Rightarrow x\cdot\left(x+1\right)=306\)

\(\Rightarrow x^2+x=306\)

\(\Rightarrow x^2+x-306=0\)

\(\Rightarrow x^2+18x-17x-306=0\)

\(\Rightarrow\left(x^2+18x\right)-\left(17x+306\right)=0\\ \Rightarrow x\left(x+18\right)-17\left(x+18\right)=0\\ \Rightarrow\left(x-17\right)\left(x+18\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x-17=0\\x+18=0\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=17\\x=-18\end{matrix}\right.\\ \text{Vậy, x }\in\left\{-18;17\right\}.\)

\(x\left(x+1\right):2=153\)

\(x\left(x+1\right)=306\)

\(x^2+x=306\)

\(x=17;x=-18\)

\(x\cdot\left(x+1\right):2=153\)

\(\Rightarrow x\left(x+1\right)=153\cdot2\)

\(\Rightarrow x^2+x=306\)

\(\Rightarrow x^2+x-306=0\)

\(\Rightarrow x^2+18x-17x-306=0\)

\(\Rightarrow x\left(x+18\right)-17\left(x+18\right)=0\)

\(\Rightarrow\left(x-17\right)\left(x+18\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=17\\x=-18\end{matrix}\right.\)

Trường hợp 1 :

2.3^x + 5.3^x+1 = 153

=> 2.3^x + 5.3^x + 3 = 153

=> (2 + 5).3^x = 150

=> 7.3^x = 150 

=> 3^x = 150/7 => x không thỏa mãn

Trường hợp 2 :

2.3^x + 5.3^x + 1 = 153

=> (2 + 5).3^x = 152

=> 7 . 3^x = 152

=> 3^x= 152/7 => x không thỏa mãn

Nếu bạn không gõ latex thì 2 trường hợp cũng sẽ xảy ra :((

1 + 2 + 3 + .... + x = 153

x(x+ 1) = 153 x 2 = 306

x(x + 1) = 17 x (17 + 1)

Vậy x= 17 

Ta có: (1+X).X:2= 153

=> (1+X).X= 153.2

=> (1+X).X= 306

Vì 306= 22.23

=> X=22

mình nha bạn

1)
\(4x^2-4x+1-4x^2-16x-16=9\)
\(-20x-15=9\)
-20x=24
x=-1,2

3)
(2x+1)²=5²
2x+1=5
2x=4
x=2
 

\(1,\Rightarrow4x^2-4x+1-4x^2-16x-16=9\\ \Rightarrow-20x=23\Rightarrow x=-\dfrac{23}{20}\\ 2,\Rightarrow9x^2-6x+1+2x+6+11-11x^2=15\\ \Rightarrow2x^2+4x-3=0\\ \Rightarrow2\left(x^2+2x+1\right)-5=0\\ \Rightarrow2\left(x+1\right)^2-5=0\\ \Rightarrow\left[\sqrt{2}\left(x+1\right)-\sqrt{5}\right]\left[\sqrt{2}\left(x+1\right)+\sqrt{5}\right]=0\\ \Rightarrow\left[{}\begin{matrix}\sqrt{2}\left(x+1\right)=\sqrt{5}\\\sqrt{2}\left(x+1\right)=-\sqrt{5}\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x+1=\sqrt{\dfrac{5}{2}}=\dfrac{\sqrt{10}}{2}\\x+1=-\sqrt{\dfrac{5}{2}}=\dfrac{-\sqrt{10}}{2}\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{\sqrt{10}-2}{2}\\x=\dfrac{-\sqrt{10}-2}{2}\end{matrix}\right.\)

\(3,\Rightarrow\left(2x+1\right)^2-25=0\Rightarrow\left(2x+1-5\right)\left(2x+1+5\right)=0\\ \Rightarrow\left[{}\begin{matrix}2x=4\\2x=-6\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=2\\x=-3\end{matrix}\right.\)

\(4,\Rightarrow x^3+3x^2+3x+1-x^3-2x^2-2x+1-x^2=15\\ \Rightarrow x+2=15\Rightarrow x=13\)

\(\text{(x+153)-(48-193)=1-2-3-4}\)

\(\left(x+153\right)+145=-8\)

\(x+153=-8-145\)

\(x+153=-153\)

\(x=-153-153\)

\(x=-306\)

học tốt 

(x+153)-(48-193)=1-2-3-4

(x+153)+145=-8

x+153=-8-145

x+135=-153

        x=-153-135

        x=-288

Vậy x=-288

(x +153)-(48-193)=1-2-3-4

(x+153) - 145      = -8

(x+153) -145       = 8 -145

x +153                 = 153

x                          = 153 -153

x                           = 0

CHÚC BẠN HỌC TỐT

X x 3= 153                                     X : 2 = 320

X       = 153 : 3                               X       = 320 x 2

 X       = 51                                      X       = 640

A,(X+153)-(48+193)=1-2-3-4:

x+153-48-193=1-2-3-4

     x+(-88)=-8

      x-88=-8

       x=-8+88=80

Ta có : \(\frac{1-x}{x}+1=x\)

Vậy \(\frac{\left(x+1\right).x}{2}=153\)

(x+1)x=153.2

(x+1)x=306

=> x=17

tim so so hang ban nhe