Before radar and sonar, sailors would climb to the top of their ships to watch for land or changes in weather. If the lookout at the top of the mast can see an island six miles away, about how tall is the mast? Round your answer to the nearest whole number if necessary. Use the formula for the relationship between height (h) and visibility, how far you can see, (d): 5/6 sqrt of h

He gained 60,900 dollars for that land

So the first thing we do is to multiply the top equation by 3. the reason i want to do this is i notice there will be a 6y on both equations and can possibly add/subtract them. so we get 6y = -3x + 27. adding that and the second equation we get 6x = 27-15 which is 12. divide by 6 and we get 2. ∴ x = 2. substituting 2 into the first equation we get 2y = -2 + 9 which is 7. divide by 2 and we get 7/2. ∴ y = 7/2, x = 2.