Question

How do you solve a triangle if you are given A = 120 degrees, b = 3, c = 10?

Answer 1

`color(brown)(c = sqrt139 = 11.79 " units"`

Explanation:

`hat A = 120, b = 3, c = 10, a = ?`

Applying the Law of Cosines,

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

`a^2 = 3^2 + 10^2 - (2 * 3 * 10 * cos (120)) = 139`

`color(brown)(c = sqrt139 = 11.79 " units"`