6B 7C 8D 9C 10C 11D 12D 13B 14A 16B 17A 18A 19B 20C 21A 22B 23D 24B 25A 26C 27B 28A 29D 30B 31D

6B,7C,8D,9C,10C,11D,12D,13B,14A,16B,17A,18A,19B,20C,21A,22B,23D 24B,25A,26C,27B,28A,29D,30B,31D

I.

1A 2D 3B 4C

II.

5D 6A 7B 8B

III.

9B 10B 11A

IV.

12A 13B 14A

15C 16B 17B 18A 19B 20C 21D 22C 23B 24D 

Help

bạn ơi bạn chụp cả đáp án A nữa, ko có sao mk giúp đc

1 g

2 a

3 f

4 c

5 b

6 h

7 e

8 d

1 A

2 B

3 D

4 A

5 B => reading

6 B => who sings

7 B => bored

8 B

9 B

10 C

11 C

12 B

13 A

14 C

15 B

16 C

17 D

18 C

\(x^2+20x+100=\left(x+10\right)^2\)

\(16x^2+24xy+\left(3y\right)^2=\left(4x+3y\right)^2\)

\(y^2-14y+49=\left(y-7\right)^2\)

\(a,\) \(x^2+20x+100=\left(x+10\right)^2\)

\(b,\) \(16x^2+24x+9=\left(4x+3\right)^2\)

\(c,\) \(y^2-14x+49=\left(y-7\right)^2\)

b b c a d

1 B

2 B

3 D

4 A

5 D

c: \(C=\left(x+y\right)^2-\left(x-y\right)^2\)

\(=\left(x+y+x-y\right)\left(x+y-x+y\right)\)

=4xy

d: \(D=\left(\dfrac{x}{2}-y\right)\left(\dfrac{x}{2}+y\right)=\dfrac{1}{4}x^2-y^2\)