In order to apply the law of cosines to find the length of the side of a triangle, it is enough to know which of the following ?

the area of a triangle ?

the measure of an angle and the length of the side opposite that angle ?

the lengths of the two triangle sides and the measure of the angle between them ?

Third one is right.

Two sides and the angle between them.

The cosine trigonometric function is defined as:

cos(x) = adjacent/hypotenuse

I.e. the cosine of an angle (within a right-angle triangle) is equal to the ratio of the adjacent side (to the angle) to the hypotenuse, where the angle is one the two that is not the right-angle.

If you illustrate this, you can observe that the components of the cosine on a diagram are always the two sides that create the angle and therefore the angle will naturally be between these two sides.

C.

the lengths of the two triangle sides and the measure of the angle between them

Step-by-step explanation:

a p e x

2

step-by-step explanation: