\(\Leftrightarrow x^2-8x+16-x^2+4=2\\ \Leftrightarrow-8x=-18\\ \Leftrightarrow x=\dfrac{9}{4}\)

\(2\times x+\dfrac{x}{2}=10\)

\(x\times\left(2+\dfrac{1}{2}\right)=10\)

\(x\times\left(\dfrac{4}{2}+\dfrac{1}{2}\right)=10\)

\(x\times\dfrac{5}{2}=10\)

\(x=10\div\dfrac{5}{2}\)

\(x=4\)

X x 2 + X/2=10

X x 2 + X x 0,5=10

X x (2+0,5)      =10

X x 2,5            =10

X                     =10:2,5

X                     =4

NHỚ TICK CHO MÌNH NHA ☘

\(x:\left(-2\right)^5=\left(-2\right)^3\\ \Rightarrow x=\left(-2\right)^3.\left(-2\right)^5\\ \Rightarrow x=\left(-2\right)^8\\ \Rightarrow x=2^8\)

sorry ạ

a) x - 1/2 = 3/5

x = 3/5 + 1/2

x = 11/10

b) x - 1/2 = -2/3

x = -2/3 + 1/2

x = -1/6

c) 2/5 - x = 0,25

x = 2/5 - 0,25

x = 2/5 - 1/4

x = 3/20

`x xx 2 +x/2=10`

`=> x xx 2+ x xx 1/2 =10`

`=> x xx (2+1/2) =10`

`=> x xx ( 4/2 +1/2) =10`

`=> x xx 5/2 =10`

`=> x=10:5/2`

`=> x= 10 xx 2/5`

`=> x= 20/5`

`=>x=4`

Vậy `x=4`

bài lớp 4 gì mà khó vậy. Lớp 5 còn chưa giải được

\(x^4-3x+2=\left(x-1\right)\left(x^3+bx^2+ax-2\right)\)

\(\Leftrightarrow x^4-3x+2=x^4+bx^3+ax^2-2x-x^3-bx^2-ax+2\)

\(\Leftrightarrow x^4-3x+2=x^4+\left(b-1\right)x^3+\left(a-b\right)x^2+\left(-2-a\right)x+2\) 

\(\Leftrightarrow x^4+0x^3+0x^2-3x+2=x^4+\left(b-1\right)x^3+\left(a-b\right)x^2+\left(-2-a\right)x+2\)

Ta có: \(\left\{{}\begin{matrix}b-1=0\\a-b=0\\-2-a=-3\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}b=1\\a=b\\a=1\end{matrix}\right.\)

\(\Leftrightarrow a=b=1\)  

Vậy: ... 

ta có \(\left(x+2\right)^2-2\left(x+2\right)\left(x+3\right)+\left(x+5\right)^2=7\)

\(\Leftrightarrow x^2+4x+4-2\left(x^2+5x+6\right)+x^2+10x+25=7\)

\(\Leftrightarrow4x+10=0\Leftrightarrow x=-\frac{5}{2}\)

Bạn áp dụng hằng đẳng thức số 1, nhân phá ngoặc là Ok nhé

\(\left(x+2\right)^2-2\left(x+2\right)\left(x+3\right)+\left(x+5\right)^2=7\)

\(\Leftrightarrow x^2+4x+4-2\left(x^2+3x+2x+6\right)+x^2+10x+25-7=0\)

\(\Leftrightarrow2x^2+14x+22-2x^2-6x-4x-12=0\)

\(\Leftrightarrow4x+10=0\)

\(\Leftrightarrow4x=-10\)

\(\Leftrightarrow x=\frac{-5}{2}\)

Trả lời:

( x + 2 )² - 2 ( x + 2 ) ( x + 3 ) + ( x + 5 )² = 7

<=> x² + 4x + 4 - 2 ( x² + 5x + 6 ) + x² + 10x + 25 = 7

<=> x² + 4x + 4 - 2x² - 10x - 12 + x² + 10x + 25 =  7

<=> 4x + 17 = 7

<=> 4x = - 10

<=> x = - 5/2

Vậy x = - 5/2 là nghiệm của pt.

\(\Leftrightarrow x^2-6x+9-x^2+4=1\)

=>-6x=-12

hay x=2

\(\left(x-1\right)\left(x+2\right)=\left(x-2\right)^2\)

\(\Rightarrow\left(x-1\right)x+\left(x-1\right)2=\left(x-2\right)\left(x-2\right)\)

\(\Rightarrow x^2-x+2x-2=\left(x-2\right)x-\left(x-2\right)2\)

\(\Rightarrow x^2+x-2=x^2-2x-\left(2x-4\right)\)

\(\Rightarrow x^2+x-2=x^2-2x-2x+4\)

\(\Rightarrow x^2+x-x^2+2x+2x=4+2\)

\(\Rightarrow5x=6\)

\(\Rightarrow x=\frac{6}{5}\)