Respuesta :

It is a linear pair of angles hence supplementary

[tex]\\ \tt\hookrightarrow 123+3x=180[/tex]

[tex]\\ \tt\hookrightarrow 3x=180-123[/tex]

[tex]\\ \tt\hookrightarrow 3x=57[/tex]

[tex]\\ \tt\hookrightarrow x=19[/tex]

Explanation:

The angles shown is supplementary because the sum of 123 and 3x is 180.

Thus, the equation formed:

  • 123 + 3x = 180°

Subtract 123 both sides:

  • 123 + 3x = 180°
  • => 123 - 123 + 3x = 180 - 123
  • => 3x = 57

Divide 3 both sides:

  • => x = 57/3 = 19

The value of x is 19.