Question

Tìm x : (2x−5)(x 2)−2x(x−1)=15

Answer 1

 PT: x(5-2x)+2x(x-1)=15 
<=> 5x - 2x² + 2x² - 2x = 15 
<=> 3x = 15 
<=> x = 5.

Answer 2

\(\left(2x-5\right)\left(x+2\right)-2x\left(x-1\right)=15\)

\(\Leftrightarrow\left(2x^2+4x-5x-10\right)-2\left(x^2-x\right)-15=0\)

\(\Leftrightarrow2x^2-x-10-2x^2+2x-15=0\)

\(\Leftrightarrow x=25\)

Answer 3

  (2x-5)(x2)-2x(x-1)=15

 \(2x^2-10-2x^2+2x=15\)

 \(-10+2x=15\)

 \(-8x=15\)

       \(x=-\frac{15}{8}\)