Question

This is a law of cosines please help me solve it

Answer 1

Given:

In ΔKLM,

k = 24, m = 16 and ∠L = 25°

To find:

The length of l.

Solution:

Using law of cosine:

$l^2=k^2+m^2-2km \cdot \cos L$

Substitute the given values in the formula.

$l^2=24^2+16^2-2\times 24\times 16 \cdot \cos 25^\circ$

The value of cos 25° = 0.906

$l^2=576+256-768\cdot(0.906)$

$l^2=832-695.808$

$l^2=136.192$

Taking square root on both sides.

$l=11.6$

The length of l is 11.6.