Respuesta :

Answer:

The answer to your question is: 20°

Step-by-step explanation:

Data

m∠XZY = 40

m∠XZB = 20

Process

1.- Find the measure of ∠ XAB

   ∠XAB = 40°   because AB ║ YZ

2.- Find the measure of ∠ZAB

     ∠ZAB + ∠XAB = 180

    ∠ZAB = 180 - ∠XAB

    ∠ZAB = 180 - 40

    ∠ZAB = 140°

3.- Find the measure of ∠ABZ

    The sum of the internal angles in a triangle equals 180°

     ∠AZB + ∠ZAB + ∠ABZ = 180

     20° + 140° + ∠ABZ = 180

     ∠ABZ = 180 - 20 - 140

    ∠ABZ = 20°