Question

Tìm x biết:

(3+6+x) . 9 = (2-x).2

(6-x) . 3 = (9+x) . 3

 

Answer 1

Bài làm

( 3 + 6 + x ) . 9 = ( 2 - x ) . 2

27 + 54 + 9x = 4 - 2x

9x + 2x = 4 - 27 - 54

11x = -77

x = -7

Vậy x = -7

b) ( 6 - x ) . 3 = ( 9 + x ) . 3

18 - 3x = 27 + 3x

-3x - 3x = 27 - 18

-6x = 9

x = 9/-6

x = -3/2

Vậy x = -3/2

Answer 2

a,\(\text{(3+6+x) . 9 = (2-x).2}\)

\(27+54+9x=4-2x\)

\(9x+2x=4-54-27\)

\(11x=-77\)

\(\Rightarrow x=-7\)

b, \(\text{(6-x) . 3 = (9+x) . 3}\)

\(18-3x=27+3x\)

\(-3x-3x=27-18\)

\(-6x=9\)

\(\Rightarrow x=\frac{9}{-6}\)

học tốt

Answer 3

\(\left(3+6+x\right)9=\left(2-x\right)2\)

\(27+54+9x=4-2x\)

\(27+54+9x-4+2x=0\)

\(77+11x=0\)

\(11x=-77\)

\(x=-7\)

\(\left(6-x\right)3=\left(9+x\right)3\)

\(18-3x=27+3x\)

\(18-3x-27-3x=0\)

\(-9-6x=0\)

\(6x=-9\)

\(x=-\frac{3}{2}\)

Answer 4

(3+6+x) . 9 = (2-x).2

81 + 9x = 4 - 2x

81 - 4 = - 2x - 9x

77 = -11x

  x = 77:(-11)

 x = -7

(6-x) . 3 = (9+x) . 3

18-3x=27+3x

 -3x-3x=27-18

     -6x=9

       x=9:(-6)

       x=-1,5