Question

Tìm x:

(6x-5)(x+2)-6x² =8

Giúp há há=))

Answer 1

(6x - 5)(x + 2) - 6x² = 8

=> 6x(x + 2) - 5(x + 2) - 6x² = 8

=> 6x² + 12x - 5x - 10 - 6x² = 8

=> (6x² - 6x²) + (12x - 5x) - 10 = 8

=> 7x - 10 = 8

=> 7x = 18

=> x = 18/7

Answer 2

\(\left(6x-5\right)\left(x+2\right)-6x^2=8\)

\(\Leftrightarrow6x.\left(x+2\right)-5.\left(x+2\right)-6x^2=8\)

\(\Leftrightarrow6x^2+12x-5x-10-6x^2=8\)

\(\Leftrightarrow\left(6x^2-6x^2\right)+\left(12x-5x\right)-10=8\)

\(\Leftrightarrow7x-10=8\Leftrightarrow x=\frac{18}{7}\)

Answer 3

\(6x^2+12x-5x-10-6x^2=8\) 

\(7x-10=8\) 

\(7x=18\) 

\(x=\frac{18}{7}\)

Answer 4

( 6x - 5 )( x + 2 ) - 6x² = 8

<=> 6x² + 7x - 10 - 6x² = 8

<=> 7x - 10 = 8

<=> 7x = 18

<=> x = 18/7

Answer 5

\(\left(6x-5\right)\left(x+2\right)-6x^2=8\)

\(6x^2+12x-5x-10-6x^2=8\)

\(x^2+12x-5x-10-6x^2-8=0\)

\(7x-18=0\)

\(7x=18\)

\(x=\frac{18}{7}\)