a) (x-2)²=9

$\iff$ $\{\begin{array}{c}x+2=3\\ x+2=-3\end{array}$ $\iff$ $\{\begin{array}{c}x=1\\ x=-5\end{array}$ vậy $x=1;x=-5$

b) (x-3)²-3x+9=0

301 dung 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000%

= x*4+x*2

= x*6

= 18 nha

1/2 là đúng

800000 m nha

       Bài giải

số kg gạo đóng vào 9 bao là :

       5 x 9 = 45 ( kg )

Mỗi bao 3kg thì đóng được số bao là :

    45 : 3 = 15 ( bao )

           Đáp số : 15 bao

191 tia

Vì cô ấy cởi áo mưa

kết quả là 48 còn đầu tư làm nha