What does 2n - 6 =-28 mean

What is the value of x? enter your answer in the box. (cm)

Angela rode his bike around a bike trail that was 1/4 of a mile long he rode his bike around the trail 8 * angelo says he wrote a total of 8/4 miles to russell says he's wrong and he actually and says that he actually wrote to my who is corrupt use words and trying to explain how you know.

Iam a rectangle. my perimeter is 60 feet. how much are do i cover?