HELP ME PLEASE
Find x i have no idea how to do trigonometry

Gabriel determined that his total cost would be represented by 2.5x + 2y – 2. his sister states that the expression should be x + x + 0.5x + y + y – 2. who is correct? explain.

An archaeologist in turkey discovers a spear head that contains 53% of its original amount of c-14. find the age of the spear head to the nearest year. (5250 isn’t right)

Find the quotient 9(cos135+isin135)/7(cos10+isin10)