in the first question you use the cosine rule to solve the problem since you have one angle and two sides of the triangle and the rules states thus x square is equal to 5 squid + 8 squared -2 * 5 * 8 x cos 60
Answer and workings in the attachment below. Also, do me one big favour. Let me know if it's the answer your teacher or text book ends up giving you. That would give me some satisfaction.
