Question

Em nhờ mn giải giúp ạ gấp ạ Em cảm ơn ạ

Answer 1

1.B

2.C

3.B

4.B

5.D

 

Answer 2

1.B

2.C

3.B

4.B

5.D

6.A

7.B

8.A

 

Answer 3

 

9a) 4x-12=0

(=)x=3

9b)2x(x+9)-6(x+9)=0

(=) (2x+6)(x+9)=0

\(\left[{}\begin{matrix}2x+6=0\\x+9=0\end{matrix}\right.\)

\(\left[{}\begin{matrix}x=-3\\x=-9\end{matrix}\right.\)

Answer 4

9c) 5x+20=0

<=> 5x=-20

<=> x=-4

9d)2x(3x+9)-6(3x+9)=0

<=>(2x-6)(3x+9)=0

<=>\(\left[{}\begin{matrix}2x-6=0\\3x+9=0\end{matrix}\right.\)

<=>\(\left[{}x=-3}\)

Answer 5

9e) |2x-3|=6x+5

TH1:|2X-3|=2X-3 nếu 2x-3\(\ge0\)

2x-3=6x+5 <=> x=-2(t/m)

TH2: |2X-3|=-(2X-3) nếu 2x-3<0

-2x+3=6x+5 <=> x=-1/4 (ktm)