=>    5 chia het cho x+1

          =>    x+1 E U(5) ={-1;1;5;-5}

          =>    xE { -2;0;4;-6}

        Do (x+1)(y+2)=5

           => 5 cung chia het cho y+2

           => y+2 E U(5)={-1;1;5;-5}

           =>  y E{ -3;-1;3;-7}

\(82-\left(x+15\right)=60\)

\(\Leftrightarrow82-x-15=60\)

\(\Leftrightarrow-x=60-82+15=-7\)

\(\Leftrightarrow x=7\)

\(82-\left(x+15\right)=60\)

\(\Leftrightarrow-x-15=-22\)

\(\Leftrightarrow x=-\left(-22+15\right)\)

\(\Leftrightarrow x=7\)

82 - (x + 15) = 60

          x + 15 = 82 - 60

          x + 15 = 22

                   x = 22 - 15

                   x = 7               

=>1/5x+3x=60

=>3,2x=60

hay x=18,75

`=> 3,2 x = 60`

`=> x = 18,75`.

`x : 5 + x xx 3 = 60`

`x xx 1/5 + x xx 3 = 60`

`x xx (1/5 + 3) = 60`75/4`

`x xx 16/5 = 60`

`x               = 60 : 16/5`

`x                = 75/4`

12,3:x-4,5:x=15

(12,3-4,5):x=15

7,8:x=15

      x=7,8:15

     x=13/25=0,52

chúc bạn học tốt !!!

\(x=\frac{1}{\sqrt[3]{4-\sqrt{15}}}+\sqrt[3]{4-\sqrt{15}}\)

<=> \(x^3=\frac{1}{4-\sqrt{15}}+3\left(\frac{1}{\sqrt[3]{4-\sqrt{15}}}+\sqrt[3]{4-\sqrt{15}}\right)\left(\frac{1}{\sqrt[3]{4-\sqrt{15}}}.\sqrt[3]{4-\sqrt{15}}\right)\)

                           \(+4-\sqrt{15}\)

<=> \(x^3=\frac{1}{4-\sqrt{15}}+4-\sqrt{15}+3x\)

<=> \(x^3-3x+2006=\frac{1}{4-\sqrt{15}}+4-\sqrt{15}+2006\)

<=> \(x^3-3x+2006=\frac{4+\sqrt{15}}{16-15}+4-\sqrt{15}+2006\)

<=> \(x^3-3x+2006=2014\)

\(\left(x+3\right)^2+\left(0,5y-1\right)^2=0\)

Do \(\left(x+3\right)^2\ge0;\left(0,5y-1\right)^2\ge0\)

\(\Rightarrow\left(x+3\right)^2+\left(0,5y-1\right)^2=0\)

\(\Leftrightarrow\hept{\begin{cases}\left(x+3\right)^2=0\\\left(0,5y-1\right)^2=0\end{cases}\Leftrightarrow}\hept{\begin{cases}x+3=0\\0,5y-1=0\end{cases}\Leftrightarrow}\hept{\begin{cases}x=-3\\y=2\end{cases}}\)

...

Vì \(\hept{\begin{cases}\left(x+3\right)^2\ge0\forall x\\\left(0.5y-1\right)^2\ge0\forall y\end{cases}}\)

\(\Rightarrow\left(x+3\right)^2+\left(0.5y-1\right)^2\ge0\forall x,y\)

Mà \(\left(x+3\right)^2+\left(0.5y-1\right)^2=0\)

\(\Rightarrow\hept{\begin{cases}x+3=0\\0.5y-1=0\end{cases}\Leftrightarrow}\hept{\begin{cases}x=-3\\y=2\end{cases}}\)

Vậy ...

\(\left|X-15\right|=2\)

\(\orbr{\begin{cases}X-15=-2\\X-15=2\end{cases}\Leftrightarrow\orbr{\begin{cases}X=-2+15=-13\\X=2+15=17\end{cases}}}\)

VẬY X=-13 HOẶC X=17

/x-15/=2

\(\Rightarrow\)/x/=2+15

\(\Rightarrow\)/x/=17

suy ra hoặc x=17

hoặc x=-17

\(\frac{15}{25}=\frac{3}{5}\)

k cho mik nha các bn làm ơn 

Ta có: 15/25 = 5.3/5.5 = 3/5

Câu này khó vậy ak

Ta có : 15 và 25 cùng chia hết cho 5.

15:5=3; 25:5=5

=> 15/25=15:5/25:5=3/5