\(\left(\dfrac{3}{5}\right)^5.x=\left(\dfrac{3}{7}\right)^7\)

\(x=\left(\dfrac{3}{7}\right)^7:\left(\dfrac{3}{5}\right)^5\)

\(x=\dfrac{3^7}{7^7}\times\dfrac{5^5}{3^5}=\dfrac{3^7.5^5}{7^7.3^5}=\dfrac{9.5^5}{7^7}\)

tick mị nhé

- 12.[ x - 5 ] + 7.[ 3 - x ] = 5

=> - 12x + 60 + 21 - 7x = 5

=> ( - 12x - 7x ) + 60 + 21 = 5

=> - 19x + 81 = 5

=> - 19x = 5 - 81

=> - 19x = - 76

=> x = ( - 76 ) : ( - 19 )

=> x = 4

Vậy x = 4

-12(x-5)+7(3-x)=5

<=>(-12x)-(-60)+21-7x=5

<=>(-12x)+60+21-7x=5

<=>(-12x-7x)+81=5

<=>(-19x)=5-81=-76

<=>x=(-76):(-19)

<=>x=4

VẬy x=4

sẽ bằng: -12.x-(-12).5+7.3-7.x=5

= -12x+60+21-7x=5

Áp dụng quy tắc chuyển vế ta sẽ có

-12x-7x= 5-60-21= -76

-19x= -76 => x= -76/-19=4

\(\left(\frac{3}{5}.x-\frac{2}{3}.x-x\right).\frac{1}{7}=\frac{-5}{21}\)

\(\Rightarrow x.\left(\frac{3}{5}-\frac{2}{3}-1\right).\frac{1}{7}=\frac{-5}{21}\)

Tính trong ngoặc trước rồi qui ra <=> Tính nốt đi !!!

Tính nốt cho ๖ۣۜҨž乡тяầи♚νăи♚нùиɢ❦

\(\left(\frac{3}{5}-\frac{2}{3}-1\right)x.\frac{1}{7}=-\frac{5}{21}\)

\(\Rightarrow x.\frac{-16}{15}=-\frac{5}{21}:\frac{1}{7}\)

\(\Rightarrow x.-\frac{16}{15}=-\frac{5}{3}\)

\(\Rightarrow x=-\frac{5}{3}:-\frac{16}{15}\)

\(\Rightarrow x=\frac{25}{16}\)

X x 3/5+ Xx 3/7=31/70

=>X x (3/5+3/7)=31/70

=>X x 36/35=31/70

=>X=31/70:36/35

=>X=31/72

X x 3/5+ Xx 3/7=31/70

=>X x (3/5+3/7)=31/70

=>X x 36/35=31/70

=>X=31/70:36/35

=>X=31/72

X x 3/5+ Xx 3/7=31/70

=>X x (3/5+3/7)=31/70

=>X x 36/35=31/70

=>X=31/70:36/35

=>X=31/72

A) Ta có: \(\frac{\left(x+1\right)x}{2}=16290\)

=> \(\left(x+1\right)x=32580\)

Sau đó tự tìm

b) \(7^{x+3}+7^{x+5}=17150\)

\(7^{2x+8}=17150\)

Tự tính tiếp nhé

\(-12\times\left(x-5\right)+7\times\left(3-x\right)=5\)

\(-12\times x+12\times5+7\times3-7\times x=5\)

\(x\times\left(-12-7\right)+\left(60+21\right)=5\)

\(x\times\left(-19\right)+81=5\)

\(x\times\left(-19\right)=5-81\)

\(x\times\left(-19\right)=-76\)

\(x=\frac{-76}{-19}\)

\(x=4\)

Chúc bạn học tốt

-12 ( x - 5 ) + 7 ( 3 - x ) = 5

-12x - ( -12 ) . 5 + 7 . 3 - 7x = 5

-12x - ( - 60 ) + 21 - 7x = 5

-12x - 7x - ( - 60 ) + 21 = 5

x . ( - 12 - 7 ) - [( - 60 ) - 21 )] = 5

-19x - ( - 81 ) = 5

-19x = 5 + ( -81 )

-19x = -76

      x = (-76) : ( -19)

      x = 4

Vậy x = 4

\(-12\left(x-5\right)+7\left(3-x\right)=5\)

\(-12x+60+21-7x=5\)

\(-12x-7x=5-60-21\)

\(-19x=-76\)

\(x=4\)

Ta có: \(\frac{x-3}{x+5}=\frac{5}{7}\)

\(\Rightarrow7.\left(x-3\right)=5.\left(x+5\right)\)

\(\Rightarrow7x-21=5x+25\)

\(\Rightarrow7x-5x=21+25=46\)

\(\Rightarrow2x=46\)

\(\Rightarrow x=46:2=23\)

Vậy x = 23

Ủng hộ mik nha!

-12x+60+21-7x=5

-12x-7x=-60-21+5

-19x=-76

x=4

-12.x + 12.5+7.3-7.x=5

-12.x+ 60+21-7.x=5

-19.x=76

=> không có x