Question

a) (2600+6400)-3.x=1200b) (( 6.x-72)/2-84). 28=5628c) 2x-138 =2³.3²

^{d) 42x=39.42-37.42}

^{làm dùng minh nhé. dễ lắm}

Answer 1

a.(2600+6400)-3.x=1200

9000-3.x=1200

3.x=9000-1200

3.x=7800

x=7800/3

x=2600

Vậy x=2600

Answer 2

b.[(6.x-72):2-84].28=5628

(6.x-72):2-84=5628:28

(6.x-72):2-84=201

(6.x-72):2=201+84

(6.x-72):2=285

6.x-72=285.2

6.x-72=570

6.x=570+72

6.x=642

x=642:6

x=107

vậy x=107

Answer 3

c.2x-138=\(2^3\).\(3^2\)

2x-138=8.9

2x-138=72

2x=72+138

2x=210

x=210:2

x=105

vậy x=105

Answer 4

d.42x=39.42-37.42

42x=37.(42-42)

42x=37.0

42x=0

x=0

vậy x=0