Answer:
The answer to your question is: 20°
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°