Question

2x + 1 = 15 

2x - 3 = 17 . 1 mũ 30 

20 + 8 (x - 3) = 5 mũ 2 . 4

x mũ 2 - 7 = 9 

x + 6  = 4 mũ 5 : 4 mũ 3

3 mũ 2 (15 - 2x) - 5 mũ 2 = 5. 2 mũ 2

Answer 1

1)

2x + 1 = 15

2x = 15 - 1

2x = 14

x = 14 : 2

x = 7

2)

2x - 3 = 17 x 1³⁰

2x - 3 = 17

2x = 17 + 3 

2x = 20

x = 20 : 2

x = 10

3)

20 + 8 (x - 3) = 5² x 4  

20 + 8 (x - 3) = 25 x 4

20 + 8 (x - 3) = 100

8 (x - 3) = 100 - 2

8 (x + 3) = 80

x - 3 = 80 : 8

x - 3 = 10

x = 10 + 3

x = 13 

4)

x² - 7 = 9  

x² = 9 + 7

x² = 16  

x² = 4²

x = +-4

=>(x = 4 ; x = -4)

5)

x + 6 = 4⁵:4³

x + 6 = 4²

x + 6 = 16

x = 16 - 6

x = 10

6)

3²(15 - 2x) - 5² = 5 x 2²

9(15 - 2x) - 25 = 5 x 4

9(15 - 2x) - 25 = 20

9(15 - 2x) = 20 + 25

9(15 - 2x) = 45

15 - 2x = 45 : 9

15 - 2x = 5

2x = 15 - 5

2x = 10

x = 10 : 2

x = 5

Answer 2

`2x + 1 = 15`

`2x = 14`

`x = 7`

`2x - 3 = 17 . 1`

`2x = 20`

`x = 10`

`x^2 - 7 = 9`

`x^2 = 16`

`x = 4.`

`x + 6 = 4^5 : 4^3`

`x + 6 = 16`

`x = 10`

`3^2(15-2x) - 5^2 = 5 . 4`

`9(15 - 2x) - 25 = 20`

`15 - 2x = 5`

`2x = 10`

`x = 5`