Free throw line from basketball rim is 15 feet. The rim is twice the size of a basketball measuring across. A basketball is 9 - 9 1/2 inches long. So that means that the free throw line from the backboard is 16 feet 6 inches, or 16 feet 7 inches.
The rim is the circular hoop attached perpendicularly to the backboard. The rim is usually painted orange and is made of iron. When the game first originated, a basket was used instead of a rim, which is why it is called 'basketball'.