Question

Tìm x:

\(a.\frac{3}{5}-\frac{7}{6}x=\frac{1}{30}\)

\(b.\left(-4,5-2x\right).1\frac{4}{7}=\frac{11}{4}\)

\(c.\frac{1}{3}-\frac{3}{5}:x=\frac{4}{15}\)

\(e.\frac{-6}{9}=\frac{x}{3}\)

\(f.\frac{2}{x}=\frac{x}{8}\)

 

Answer 1

c. khi và chỉ khi \(\frac{3}{5}\cdot\frac{1}{x}=\frac{1}{3}-\frac{4}{15}=\frac{1}{15}\)

                        \(\frac{1}{x}=\frac{1}{15}\cdot\frac{5}{3}=\frac{1}{9}\)

suy ra x=9

Answer 2

a,7/6x=3/5-1/30

7/6x=17/30

x=17/30:7/6

x=17/35

b,(-9/2-2x).11/7=11/4

-9/2-2x=11/4:11/7

-9/2-2x=7/4

2x=-9/2-7/4

2x=-25/4

x=-25/4:2

x=-25/8

c,9

d,x=-2

e,2.8=x.x=x²

16=x²=>x=4 hoặc -4

Answer 3

a,7/6x=3/5-1/30

7/6x=17/30

x=17/30:7/6

x=17/35

b,(-9/2-2x).11/7=11/4

-9/2-2x=11/4:11/7

-9/2-2x=7/4

2x=-9/2-7/4

2x=-25/4

x=-25/4:2

x=-25/8

c,9

d,x=-2

e,2.8=x.x=x²

16=x²=>x=4 hoặc -4