Find the area of the right triangle with hypotenuse 20cm and one of the acute angle is 48°

From the above figure,

⇒ sin θ =

⇒ sin 48° =

From the sine table, sin 48° = 0.7431.

∴ 0.7431 =

∴ AB = 0.7431 × 20 = 14.862 cm

Then cos θ =

⇒ cos 48° =

From the cosine table, cos 48° = 0.6691

∴ 0.6691 =

∴ BC = 0.6691 × 20 = 13.382 cm

We know that Area of right angled triangle = 1/2 bh.

∴ Area of ΔABC = 1/2 × 13.382 × 14.862

= 99.441642

∴ Area of the triangle is 99.441 cm².