Question

If ∠P measures 27°, q equals 6.0, and r equals 7.2, then which length can be found using the Law of Cosines?

Answer 1

= 3.29

Explanation:

Let call the length needs to be found is q

We have Law of Cosine:

q =
`\sqrt{r^(2) +r^(2) -2prcosP }`

=
`\sqrt{6^(2)+7.2^(2) -2*6*7.2*cos(27)}`

= 3.29

The length can be found using the Law of Cosines is 3.29

Answer 2

We can find side RQ

Explanation:

In order to use the Law of Cosines:

-Two sides and the angle between them must be given to find the third side

-All three sides must be given to find an angle

In this case we are given two sides(q and r) and we are given angle P which is between them. Using this information we can come to the conclusion that side RQ is the length we can find.