For this case, using the law of cosine we have: c ^ 2 = a ^ 2 + b ^ 2 - 2 * a * b * cos (C) Substituting values we have: c ^ 2 = 10 ^ 2 + 8 ^ 2 - 2 * 10 * 8 * cos (105) Clearing c we have: c = root (10 ^ 2 + 8 ^ 2 - 2 * 10 * 8 * cos (105)) c = 14.33216827 round the answer to the nearest tenth: c = 14.3 Answer: the length of side c is: c = 14.3
