Respuesta :

Answer:

The number is 9

Step-by-step explanation:

• Let the number be x

[tex]{ \tt{3x - 7 = 20}} \\ [/tex]

» Add 7 to either sides following addition rule of equality:

[tex]{ \tt{(3x - 7){ \red{ + 7}} = 20{ \red{ + 7}}}} \\ { \tt{3x = 27}}[/tex]

» Divide either sides by 27:

[tex]{ \tt{ \frac{3x}{ \blue{3 }} = \frac{27}{ \blue{3}} }} \\ \\ { \tt{x = 9}}[/tex]

3x-7=20
3x=27
x=9

number is 9