tentukan bilangan berikut???

sisi miring² = 16²+12²
sisi miring² = 256+144
sisi miring² = 400
sisi miring = √400
sisi miring = 20

a)
sin a = depan / miring
= 16/20 = 4/5

b)
sec a = miring / samping
= 20/12 = 5/3

c)
tan a = depan / samping
= 16/12 = 4/3