\(3.2\times x\left(-1.2\right)\times x+2.7=-4.9\) câu a nhé

\(-5.6\times x+2.9\times x-3.86=-9.8\) câu b nhé

cảm ơn các bạn nhìu

3.2x+(-1.2)*x+2.7=-4.9

(3.2+(-1.2)*x=-4.9-2.7

2*x=-76

x=-76/2

x=-38

-5.6*x+2.9*x-3.86=-9.8

(-5.6+2.9)*x=-9.8+3.86

-27*x=-5.94

x=-5.94/-27

x=0.22

a) x vô nghĩa

b) x=0,8;x=-0,8

d: Đặt x/2=y/5=k

=>x=2k; y=5k

Ta có: xy=10

nên k²=1

Trường hợp 1: k=1

=>x=2; y=5

Trường hợp 2: k=-1

=>x=-2; y=-5

3.2​.x+1.2.x+2.7=-4.9

6.x+2.x+14=-36

(6+2).x+14=-36

8.x+14=-36

8x=-36-14

8x=-50

x=-50:8

x=-6,25

a: x=4/27-2/3=4/27-18/27=-14/27

b: =>3/4x-1/4x=1/6+7/3

=>1/2x=1/6+14/6=5/2

hay x=5

c: =>13/10x=7/2+5/2=6

=>x=13/10:6=13/60

d: (3x+2)(-2/5x-7)=0

=>3x+2=0 hoặc 2/5x+7=0

=>x=-2/3 hoặc x=-35/2

a) x = 4/27 - 2/3

    x = -14/27

a: x=4/27-2/3=4/27-18/27=-14/27

b: =>3/4x-1/4x=1/6+7/3

=>1/2x=1/6+14/6=5/2

hay x=5

c: =>13/10x=7/2+5/2=6

=>x=13/10:6=13/60

d: (3x+2)(-2/5x-7)=0

=>3x+2=0 hoặc 2/5x+7=0

=>x=-2/3 hoặc x=-35/2

a) \(x:\dfrac{6}{13}=\dfrac{13}{7}\\ \Rightarrow x=\dfrac{13}{7}.\dfrac{6}{13}\\ \Rightarrow x=\dfrac{6}{7}\)

b) \(\dfrac{4}{7}.x-\dfrac{2}{3}=\dfrac{1}{5}\\ \Rightarrow\dfrac{4}{7}.x=\dfrac{13}{15}\\ \Rightarrow x=\dfrac{91}{60}\)

c) \(\left(\dfrac{3}{10}-x\right):\dfrac{2}{5}=\dfrac{3}{5}\\ \Rightarrow\dfrac{3}{10}-x=\dfrac{6}{25}\\ \Rightarrow x=\dfrac{3}{50}\)

d) \(\dfrac{2}{3}x-\dfrac{7}{6}=\dfrac{5}{2}\\ \Rightarrow\dfrac{2}{3}x=\dfrac{11}{3}\\ \Rightarrow x=\dfrac{11}{2}\)

\(a,\)\(x:\dfrac{6}{13}=\dfrac{13}{7}\)

\(x=\dfrac{13}{7}.\dfrac{6}{13}\)

\(x=\dfrac{6}{7}\)

b,\(\dfrac{4}{7}.x-\dfrac{2}{3}=\dfrac{1}{5}\)

\(\dfrac{4}{7}.x=\dfrac{1}{5}+\dfrac{2}{3}\)

\(\dfrac{4}{7}.x=\dfrac{3}{15}+\dfrac{10}{15}\)

\(\dfrac{4}{7}.x=\dfrac{13}{15}\)

\(x=\dfrac{13}{15}:\dfrac{4}{7}\)

\(x=\dfrac{13}{15}.\dfrac{7}{4}\)

\(x=\dfrac{91}{60}\)

a: Ta có: \(x:\dfrac{6}{13}=\dfrac{13}{7}\)

\(\Leftrightarrow x=\dfrac{13}{7}\cdot\dfrac{6}{13}\)

hay \(x=\dfrac{6}{7}\)

b: Ta có: \(\dfrac{4}{7}x-\dfrac{2}{3}=\dfrac{1}{5}\)

\(\Leftrightarrow x\cdot\dfrac{4}{7}=\dfrac{13}{15}\)

hay \(x=\dfrac{91}{60}\)

x=\(\dfrac{4}{15}\) : \(\dfrac{-2}{3}\)

x=\(\dfrac{-2}{5}\)

a: Ta có: \(x\cdot\dfrac{-2}{3}=\dfrac{4}{15}\)

\(\Leftrightarrow x=\dfrac{4}{15}:\dfrac{-2}{3}=\dfrac{4}{15}\cdot\dfrac{-3}{2}=\dfrac{-2}{5}\)

b: Ta có: \(x\cdot\dfrac{-7}{19}=\dfrac{-13}{24}\)

\(\Leftrightarrow x=\dfrac{13}{24}:\dfrac{7}{19}=\dfrac{247}{168}\)

a: \(\dfrac{0.4}{x}=\dfrac{x}{0.9}\)

nên \(x^2=\dfrac{9}{25}\)

=>x=3/5 hoặc x=-3/5

b: \(\dfrac{26}{2x-1}=13\dfrac{1}{3}:1\dfrac{1}{3}\)

\(\Leftrightarrow\dfrac{26}{2x-1}=\dfrac{40}{3}:\dfrac{4}{3}=10\)

=>2x-1=13/5

=>2x=18/5

hay x=9/5

c: \(\Leftrightarrow\dfrac{2}{3}:\left(6x+7\right)=\dfrac{1}{5}:\dfrac{6}{5}\)

\(\Leftrightarrow\dfrac{2}{3}:\left(6x+7\right)=\dfrac{1}{6}\)

=>6x+7=4

=>6x=-3

hay x=-1/2

d: \(\dfrac{37-x}{x+13}=37\)

=>37(x+13)=37-x

=>37x+481=37-x

=>38x=-444

hay x=-222/19