Answer:
b
Step-by-step explanation:
sin x =
= 
This is a 3- 4- 5 right triangle
with adjacent side = 4 , then
cos x =
=
, thus
tan x =
=
=
×
= 
---------------------------------------------------
sin y = 
This is a 7- 24- 25 right triangle
with adjacent side = 24 , then
cos y =
=
, thus
tan y =
=
=
×
= 
----------------------------------------------------
tan(x - y) = 
= 
= 
= 
=
× 
=
× 
=
→ b