Question

giúp mình với ^^

Tìm x:

a) 43x =39.43-37.43

b)3x-136=2³.3²+2².5

Answer 1

a) Ta có 

43x=39.43-37.43

43x=43.(39-37)

43x=43x2

=>x=2

b) ta có

3x-136=2^3.3^2+2^2.5

3x-136=8.9+4.5

3x-136=72+20

3x-136=92

3x=228

x=76

 

Answer 2

a)  43x = 39.43 - 37.43

=> 43x = 43 . (39 - 37)

=> 43x = 43 . 2

=>     x = 43 : 43 . 2

=>     x = 1 . 2

  Vậy x = 2

Answer 3

b)  3x - 136 = 2³ . 3² + 2² . 5

=> 3x - 136 = 8 . 9 + 4 . 5

=> 3x - 136 = 72 + 20

=> 3x - 136 = 92

=> 3x          = 92 + 136

=> 3x          = 228

=>   x          = 228 : 3

Vậy x          = 76