Question

Law of cosines: a2 = b2 + c2 – 2bccos(A)

Which equation correctly uses the law of cosines to solve for the missing side length of PQR?

62 = p2 + 82 – 2(p)(8)cos(39°)
p2 = 62 + 82 – 2(6)(8)cos(39°)
82 = 62 + p2 – 2(6)(p)cos(39°)
p2 = 62 + 62 – 2(6)(6)cos(39°)

Answer 1

Answer:
yeah the second one

Explanation:

egde 2023

Answer 2

The law of Cosines:


`c^2 = a^2 + b^2 - 2ab \cos C`

`b^2 = a^2 + c^2 - 2ac \cos B`

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

Since we have a SAS triangle, we can use

`c^2 = a^2 + b^2 - 2ab \cos C`
In the law above, pretend C and
`c^2` is P and
`p^2`
a = 6 and b = 8

So this tells us that the second one it the correct answer.