Answer:
Step-by-step explanation:
m∠X + m∠Y + m∠Z = 180 {angle sum property of triangle}
3x + 5 + 40 +4x - 5 = 180
3x + 4x + 5 + 40 -5 = 180 {Combine like terms}
7x + 40 = 180 { subtract 40 from both sides}
7x = 180 - 40
7x = 140
x = 140/7
x = 20
m∠X = 3x + 5
= 3*20 + 5
= 60 + 5
m∠X = 65
m∠Z = 4x - 5
= 4*20 - 5
= 80 - 5
m∠Z = 75