A boat is 10 miles away from a lighthouse that sits on top of a coral reef with a 4 mile radius. At what angle does the captain need to steer his boat so that he avoids the boat from colliding with the underwater coral? Round to the nearest tenth degree.

At the newest animated movie, for every 9 children, there are 4 adults. there are a total of 39 children and adults at the movie.

Dylan and dusty plan to take weekly surfing lessons together. if the 2-hour lessons are $20 per person and they plan to spend $100 each on new surfboards, what is the maximum number of lessons the two can take if the total amount spent for lessons and surfboards is at most $480?

Solve the given system of equations. 2y= -x+9 , 3x-6= -15