a.(x + 125) : 312 = 14 (dư 300)

x+125 = 14 x 312 + 300

x+125 = 4 668

x= 4 668 - 125

x=4 543

b.(x-234):23=128 (dư 21)

    x-234=128 x 23 + 21

    x-234=2 965

    x=2 965 + 234

    x=3 199

c.(x-24) x 2020=2020x33

   (x-24)x2020=66 660

    x-24=66 660:2020

    x-24=33

    x=33+24

    x=57

d.5 x (x+2019)=3800 x 5

   5 x (x+2019)=19 000

   x+2019=19000:5

   x+2019=3800

   x=3800-2019

   x=1 781

HẾT=)))

a.(x + 125) : 312 = 14 (dư 300)

x+125 = 14 x 312 + 300

x+125 = 4 668

x= 4 668 - 125

x=4 543

b.(x-234):23=128 (dư 21)

    x-234=128 x 23 + 21

    x-234=2 965

    x=2 965 + 234

    x=3 199

c.(x-24) x 2020=2020x33

   (x-24)x2020=66 660

    x-24=66 660:2020

    x-24=33

    x=33+24

    x=57

d.5 x (x+2019)=3800 x 5

   5 x (x+2019)=19 000

   x+2019=19000:5

   x+2019=3800

   x=3800-2019

   x=1 781

HẾT=)))

a) \(\frac{4}{5}=\frac{28}{35}\)

b) \(\frac{12}{15}=\frac{72}{90}\)

c) \(\frac{125}{300}=\frac{5}{12}\)

d) \(\frac{6}{9}=\frac{36}{54}\)

/HT\

a) \(\frac{4}{5}=\frac{28}{35}\)      \(\text{X}=28\)

b) \(\frac{12}{15}=\frac{72}{90}\)   \(\text{X}=90\)

c) \(\frac{125}{300}=\frac{5}{12}\)  \(\text{X}=12\)

d) \(\frac{6}{9}=\frac{36}{54}\)       \(\text{X}=6\)

\(a,\)\(\frac{4}{5}=\frac{X}{35}\)

\(\Rightarrow\)\(X=35\times\frac{4}{5}\)

\(\Rightarrow\)\(X=28\)

\(b,\)\(\frac{12}{15}=\frac{72}{X}\)

\(\Rightarrow\)\(X=72\div\frac{12}{15}\)

\(\Rightarrow\)\(X=90\)

\(c,\)\(\frac{125}{300}=\frac{5}{X}\)

\(\Rightarrow\)\(\frac{5}{12}=\frac{5}{X}\)

\(\Rightarrow\)\(X=12\)

\(d,\)\(\frac{X}{9}=\frac{36}{54}\)

\(\Rightarrow\)\(\frac{X}{9}=\frac{6}{9}\)

\(\Rightarrow\)\(X=6\)

sao cía này giống toán lớp 6 vậy bn

Cái này đề sai nha bn , mk ko tính ra

😰😰😰

=>5^x=25

=>x=2

`125/5^x=5`

`-> 125/5^x=5/1`

`-> 5*5^x=125`

`->`\(5^{1+x}=125\)

`->`\(5^{1+x}=5^3\)

`->`\(x+1=3\)

`-> x=3-1`

`-> x=2`

Vậy, `5^x=5^2`.

=>5x-19+3x+24=125

=>8x+5=125

hay x=15

( 5 x − 19 ) + ( 3 x + 24 ) = 125

. 5 x − 19 + 3 x + 24 = 125

8 x + 5 = 125

8 x = 120

x = 15