Question

Câu 2: Tìm x biết:

a) 5.x-7=13                                         b)x+3^2.3=7^ 5: 7^3

c) 95-3. (x+7)=23

Answer 1

Câu 2:

a. 5.x - 7=13

=> 5.x = 13 + 7

=> 5.x = 20

=> x = 20:5

=> x = 4

b. x+3².3 = 7⁵:7³

=> x+3³ = 7²

=> x+27=49

=> x = 49-27

=> x = 22

c. 95-3.(x+7)=23

=> 3.(x+7)=95-23

=> 3.(x+7)=72

=> x+7=72:3

=> x+7=24

=> x=24-7

=> x=17

Answer 2

a) 5.x-7=13      

5.x=13+7

5.x=20

x=20:5

x=4                               

b)x+3².3=7⁵:7³ 

x+9.3=7²

x+27=49

x=49-27

x=22

c) 95-3. (x+7)=23

3.(x+7)=95-23

3.(x+7)=72

x+7=72:3

x+7=24

x=24-7

x=17

Answer 3

a) 5.x-7=13      

5.x=13+7

5.x=20

x=20:5

x=4                               

b)x+3².3=7⁵:7³ 

x+9.3=7²

x+27=49

x=49-27

x=22

c) 95-3. (x+7)=23

3.(x+7)=95-23

3.(x+7)=72

x+7=72:3

x+7=24

x=24-7

x=17

Answer 4

2.x+3^2.3=7^5:7^3