a, 14 : (0,4 + \(\dfrac{0,16}{x}\)) = 7

            0,4 + \(\dfrac{0,16}{x}\) = 14 : 7

           0,4 + \(\dfrac{0,16}{x}\) = 2

                 \(\dfrac{0,16}{x}\)  = 2 - 0,4

                   \(\dfrac{0,16}{x}\) = 1,6

                     \(x\)     = 0,16 : 1,6

                     \(x\)     = 0,1

b, 520 + 7,5 x 4 = \(x\) + \(\dfrac{174}{50}\) + 50

    520  + 30    =      \(x\) + 3,48 + 50

      \(x\) + 53,48 = 550

      \(x\)            = 550 - 53,48

      \(x\)           = 496,52

520 +7,5 x 4 = \(\frac{X+175}{5}\)+ 30

<=>520+30=\(\frac{x+175}{5}\)+30

 <=>\(\frac{X+175}{5}\)+30 = 550

<=> \(\frac{X+175}{5}\)= 520

<=> X+175 = 2600

<=> X=2425

mik chưa lm đc bài 1

k mik nha

Câu 2

520 + 7,5 . 4 =   \(\frac{x+175}{5}\)+ 30 

520 + 30 =  \(\frac{x+175}{5}\)+ 30 

 \(\frac{x+175}{5}\)= 520

x + 175 = 2600

x  = 2425 

Vậy x = 2425 

Trả lời :

Bài 1 :

\(\frac{5,7.16,2+16,2.3,7-6,2.4,8-6,2.4,6}{13,4+12,3+11,2-10,4-11,5-12,6-0,4}\)

\(=\frac{16,2.\left(5,7+3,7\right)-6,2.\left(4,8-4,6\right)}{2}\)

\(=\frac{16,2.9,4-6,2.0,2}{2}\)

\(=\frac{151,04}{2}\)

\(=75,52\)

Bài 2 :

\(520+75.4=\frac{x+175}{5}+30\)

\(520+30=\frac{x+175}{5}+30\)

\(\frac{x+175}{5}+30=550\)

\(\frac{x+175}{5}=520\)

\(\Rightarrow x+175=2600\)

\(\Rightarrow x=2425\)

Hok_Tốt

#Thiên_Hy

theo mik tính là = 5200 nha bn chúc bn học tốt ^^

\(3^{x+4}+3^x=738\)

\(\Rightarrow3^x\times3^4+3^x\times1=738\)

\(\Rightarrow3^x\left(3^4+1\right)=738\)

\(\Rightarrow3^x\times82=738\)

\(\Rightarrow3^x=738\div82\)

\(\Rightarrow3^x=9\)

\(\Rightarrow3^x=3^2\)

\(\Rightarrow x=2\)

3^x+4 + 3^x = 738

=> 3^x . 81 + 3^x = 738

=> 3^x . ( 81 + 1 ) = 738

=> 3^x . 82 = 738

=> 3^x = 9

=> 3^x = 3²

=> x = 2

\(a.\left(y.100-0,7357\right):0,01=0,55+15,88\)

\(\Leftrightarrow\left(100y-0,7357\right):0,01=16,43\)

\(\Leftrightarrow100y-0,7357=0,1643\)

\(\Leftrightarrow100y=0,9\)

\(\Leftrightarrow y=\frac{9}{1000}\)

\(b.14:\left(0,4+\frac{0,16}{y}\right)=7\)

\(\Leftrightarrow0,4+\frac{0,16}{y}=2\)

\(\Leftrightarrow\frac{0,16}{y}=1,6\)

\(\Leftrightarrow x=0,1\)

\(c.520+7,5.4=y+\frac{175}{5}+30\)

\(\Leftrightarrow520+30=y+65\)

\(\Leftrightarrow550=y+65\)

\(\Leftrightarrow y=485\)

3^x + 3^x+4 = 738

3^x.(1+3⁴) = 738

3^x.82 = 738

3^x = 9 = 3²

=> x = 2

\(3^x\)+ \(3^x\).\(3^4\)= 738\(\Rightarrow\)\(3^x\)(1+81) = 738

                                      \(\Rightarrow\)\(3^X\).82 =738

                                      \(\Rightarrow\)\(3^x\)=9=\(3^2\)

                                      \(\Rightarrow\)x=2

3^x + 3^x+4 = 738

3^x + 3^x * 3⁴ = 738

3^x + 3^x * 81 = 738

3^x( 1 + 81 ) = 738

3^x * 82 = 738

3^x = 9 

3^x = 3²

=> x = 2