Question

Tìm số tự nhiên x 

123 - 5 . ( x + 4 ) = 38

(3x - 2⁴ ) .7³  = 2.7⁴ 

Answer 1

123 - 5(x + 4) = 38

=> 5(x + 4) = 85

=> x + 4 = 17

=> x = 13

vậy_

(3x - 2⁴).7³ = 2.7⁴

=> 3x - 16 = 2.7⁴ : 7³

=> 3x - 16 = 2.7

=> 3x - 16 = 14

=> 3x = 30

=> x = 10

vậy_

Answer 2

a)123 - 5 . ( x + 4 ) = 38

5 . ( x + 4 ) = 123 - 38

5 . ( x + 4 ) = 85

x + 4 = 85 : 5

x + 4 =17

x = 13

b) ( 3x - 2^4 ) . 7^3 = 2 . 7^4

( 3x - 2^4 )  = 2 . 7^4 : 7^3

( 3x - 2^4 )  = 2 . 7

 3x - 2^4   = 14

3x - 16 = 14

3x = 30

x = 30 : 3

x = 10   

Answer 3

123 - 5.(x+4) = 38

5.(x+4) = 85

x + 4 = 17

x= 13

(3x - 2^4_).7³ = 2.7⁴

3x - 2⁴ = 14 

3x = 30

x = 10