Question

In triangle ABC, right-angled at B, AB = 24 cm, BC = 7 cm. Determine : (i) sin A, cos A (ii) sin C, cos C

Answer 1

Solution
In Δ ABC, right-angled at B ,using Pythagoras theorem we have
AC² = AB² +BC²  = 576 + 49 = 625
Or AC=25 ( taking positive value only)
Now
(i) In a right angle triangle ABC where B=90° ,
Sin A = BC/AC = 7/25
CosA = AB/AC = 24/25
(ii)
Sin C = AB/AC = 24/25
Cos C = BC/AC =7/25