Question

In ΔKLM, k = 81 cm, l = 41 cm and ∠M=93°. Find the length of m, to the nearest centimeter.

Answer 1

​ ≈93

Explanation:

S.A.S.→Law of Cosines

a^2=b^2+c^2-2bc\cos A

m^2 = 81^2+41^2-2(81)(41)\cos 93

Plug in values.

m^2 = 6561+1681-2(81)(41)(-0.052336)

Square and find cosine.

m^2 = 6561+1681+347.61542

Multiply.

m^2 = 8589.61542

Add.

√8589.61542≈92.68≈93