Question

3x (2-3x)+9x (x+1)=10

Answer 1

=6x-9x^2+9x^2+9x-10=15x-10

Answer 2

$3x(2-3x)+9x(x+1)=10$
$6x-9x^2+9x^2+9x=10$
$6x+9x=10$
$15x=10$
$x= frac{10}{15}$
$x= frac{2}{3}$
Ответ: $frac{2}{3}.$