Respuesta :

Cytokine

Since AB and BC are two parts of AC, AC = AB + BC

let's plug the expressions from the question into our equation above.

19 = 3x + 1 + 2x - 7

Combine like terms

19 = 5x - 6

Add 6 to both sides.

25 = 5x

Divide both sides by 5

5 = x

Answer:

x = 5

Step-by-step explanation:

Given that B is between A and C then

AB + BC = AC , substitute values

3x + 1 + 2x - 7 = 19 , that is

5x - 6 = 19 ( add 6 to both sides )

5x = 25 ( divide both sides by 5 )

x = 5