Question

Tìm x biết: 

5x(1 - 2x) - 3x(x +18) = 0 (có 2 giá trị x thỏa mãn)

 

Answer 1

5x(1-2x)-3x(x+18)=0

o) TH1 : 

5x(1-2x)=0

=> x(1-2x)=0

=> x-2x²=0

=> x=0

o) TH2 :

3x(x+18)=0

=> x(x+18)=0

=> x+18=0

=> x=-18

Vậy x=0 hoặc x=-18.

Answer 2

Chúc pn hc tốt

Answer 3

\(5x\left(2-2x\right)-3x\left(x+18\right)=0\)

\(\Leftrightarrow10x-10x^2-3x^2-54x=0\Leftrightarrow-44x-13x^2=0\)

\(\Leftrightarrow x\left(-13x-44\right)=0\)

TH1 : x = 0 ; TH2 : x = -44/13

Answer 4

5x( 1 - 2x ) - 3x( x + 18 ) = 0

<=> 5x - 10x² - 3x² - 54x = 0

<=> -13x² - 49x = 0

<=> -x( 13x + 49 ) = 0

<=> \(\orbr{\begin{cases}-x=0\\13x+49=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=0\\x=-\frac{49}{13}\end{cases}}\)