Answer/Step-by-step explanation:
Recall: SOHCAHTOA
✔️Sin M = Opp/Hyp
Reference angle = M
Opp = 3√21
Hyp = 15
Sin M = (3√21)/15
Sin M = √21/5
✔️Cos M = Adj/Hyp
Reference angle = M
Adj = 6
Hyp = 15
Cos M = 6/15
Cos M = 2/5
✔️Tan M = Opp/Adj
Reference angle = M
Opp = 3√21
Adj = 6
Tan M = (3√21)/6
Tan M = √21/2