Ta có: \(x=\sqrt{97-56\sqrt{3}}+\sqrt{52+16\sqrt{3}}\)

\(=\sqrt{49-2\cdot7\cdot4\sqrt{3}+48}+\sqrt{48+2\cdot4\sqrt{3}\cdot2+4}\)

\(=\sqrt{\left(7-4\sqrt{3}\right)^2}+\sqrt{\left(4\sqrt{3}+2\right)^2}\)

\(=\left|7-4\sqrt{3}\right|+\left|4\sqrt{3}+2\right|\)

\(=7-4\sqrt{3}+4\sqrt{3}+2\)

\(=9\)

Làm luôn phần y :D

y = \(\sqrt{33+20\sqrt{2}}+\sqrt{24-16\sqrt{2}}\)

y = \(\sqrt{33+2.10\sqrt{2}}+\sqrt{24-2.8\sqrt{2}}\)

y = \(\sqrt{33+2.5.2\sqrt{2}}+\sqrt{24-2.4.2\sqrt{2}}\)

y = \(\sqrt{25+2.5.\sqrt{8}+8}+\sqrt{16-2.4.\sqrt{8}+8}\)

y = \(\sqrt{\left(5+\sqrt{8}\right)^2}+\sqrt{\left(4-\sqrt{8}\right)^2}\)

y = |5 + \(\sqrt{8}\)| + |4 - \(\sqrt{8}\)| 

y = 5 + \(\sqrt{8}\) + 4 - \(\sqrt{8}\)   (Vì 4 > \(\sqrt{8}\) nên 4 - \(\sqrt{8}\) > 0)

y = 9

Vậy y = 9

Chúc bn học tốt!

16 x 3 x 21 + 24 x 2 x 52 + 12 x 4 x 27

= 48 x 21 + 48 x 52 + 48 x 27

= 48 x ( 21 + 52 + 27 )

= 48 x 100

= 4800

16 x 3 x 21 + 24 x 2 x 52 + 12 x 4 x 27

=48*21+48*52+48*27

=48*(21+52+27)

=48*100

=4800

   16 x 3 x 21 + 24 x 2 x 52 + 12 x 4 x 27

= 48 x 21 + 48 x 52  + 48 x 27

= 48 x ( 21 + 52 + 27)

= 48 x 100

= 4800

16 x 3 x 21 + 24 x 2 x 52 + 12 x 4 x 27

=48*21+48*52+48*27

=48*(21+52+27)

=48*100

=4800

4800 nha 

16 x 3 x 21 + 24 x 2 x 52 + 12 x 4 x 27

= 48 x 21 + 48 x 52 + 48 x 27

=48 x ( 21 + 52 + 27 )

=48 x 100

= 4800Thu Trang Trần

a: x-56:4=16

nên x-14=16

hay x=30

b: \(101+\left(36-4x\right)=105\)

\(\Leftrightarrow36-4x=4\)

hay x=8

Vì a: x-56:4=16

    =>x-14=16

   Hay:x=30

Vì b: 

   Hay:x=8

         Vậy x={30:8}

 Nếu sai thì thui nhá,đừng chửi mình!

a) 52 x 2 + 48 x 2

   = (52 + 48) x 2

   =     100 x 2

   = 200

b) 10 + 12 + 14 + 16 + 18 + 20

   = (12 + 18) + (14 + 16) + (20 + 10)

   =       30     +     30      +      30

   =          90

100

90

200

90

30

21

69

78

35

27

105

-13

30

21

69

78

35

27

105

623/12

1/15

5/12

2/7

4/15

1/4

=1/4

a) \(19\times\left(52+38\right)-9\times\left(52+38\right)=\)

\(=\)     \(19\times90-9\times90\) 

\(=90\times\left(19-9\right)\) 

\(=90\times10\) 

\(=900\) 

b) \(\dfrac{2}{5}\div\dfrac{3}{7}\times\dfrac{3}{7}\div\dfrac{2}{5}+2019=\)

\(=\left(\dfrac{2}{5}\div\dfrac{2}{5}\right)\times\left(\dfrac{3}{7}\div\dfrac{3}{7}\right)+2019\) 

\(=1\times1+2019\) 

\(=2019\)

                                                                                         Bài làm  

          a ) = 196

          b ) = 10 653 705

          c ) = 510 744

a) (x + 1/5)² = 9/25

=> (x + 1/5)² = (3/5)²

=> \(\orbr{\begin{cases}x+\frac{1}{5}=\frac{3}{5}\\x+\frac{1}{5}=-\frac{3}{5}\end{cases}}\)

=> \(\orbr{\begin{cases}x=\frac{2}{5}\\x=-\frac{4}{5}\end{cases}}\)

Vậy ...

\(a,\text{ }\left(x+\frac{1}{5}\right)^2=\frac{9}{25}\)

\(\left(x+\frac{1}{5}\right)^2=\left(\pm\frac{3}{5}\right)^2\)

\(x+\frac{1}{5}=\pm\frac{3}{5}\)

\(\Rightarrow\orbr{\begin{cases}x+\frac{1}{5}=\frac{-3}{5}\\x+\frac{1}{5}=\frac{3}{5}\end{cases}}\)                               \(\Rightarrow\orbr{\begin{cases}x=\frac{-3}{5}-\frac{1}{5}\\x=\frac{3}{5}-\frac{1}{5}\end{cases}}\)                   \(\Rightarrow\orbr{\begin{cases}x=-\frac{4}{5}\\x=\frac{2}{5}\end{cases}}\)

                                \(\Rightarrow\text{ }x\in\left\{-\frac{4}{5}\text{ ; }\frac{2}{5}\right\}\)

\(b,\text{ }\frac{3}{7}\cdot5-9=3x+\frac{52}{x}+16\frac{1}{7}\)

\(\frac{15}{7}-\frac{63}{7}=\frac{3x\cdot x}{x}+\frac{52}{x}+\frac{113}{7}\)

\(\frac{-48}{7}=\frac{3x^2+52}{x}+\frac{113}{7}\)

\(-\frac{48}{7}-\frac{113}{7}=\frac{3x^2+52}{x}\)

\(-\frac{161}{7}=\frac{3x^2+52}{x}\)

\(\Rightarrow\text{ }-161x=7\left(3x^2+52\right)\)

Tự làm tiếp nhé .............