Question

[Trau Van Duc]

Tìm x cần gấp

A.12:(x+4).3=6 (dấu chấm là nhân)

B.12:(x+4).3=5

C.12:(x+4).3+18=24

Answer 1

[Rinu]

Trả lời

A.12:(x+4).3=6

    12:(x+4)   =6:3

    12:(x+4)   =2

         x+4     =12:2

         x+4     =6

         x         =6-4

         x         =2

Answer 2

[Lê Trung Hiếu]

a) 12 : (x + 4).3 = 6

\(\frac{12}{\left(x+4\right)}.3=6\)

\(\frac{36}{\left(x+4\right)}=6\)

x + 4 = 36 : 6

x + 4 = 6

x = 6 - 4

x = 2

b) 12 : (x + 4).3 = 5

\(\frac{12}{\left(x+4\right)}.3=5\)

\(\frac{36}{\left(x+4\right)}=5\)

x + 4 = 36 : 5

x + 4 = \(\frac{36}{5}\)

x = \(\frac{36}{5}\) - 4

x = \(\frac{16}{5}\)

c) 12 : (x + 4).3 + 18 = 24

\(\frac{12}{\left(x+4\right)}.3+18=24\)

\(\frac{18x+108}{x+4}=24\)

18x + 108 = 24x + 96

18x + 108 - 24x = 96

-6x + 108 = 96

-6x = 96 - 108

-6x = -12

x = -12 : -6

x = 2