Solve for a:

28,000 / (1+a) = 0

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class

Aubrey read 29 books and eli read 52 books what number is equal to the number of books aubrey read?

The area of a rectangle is 10 cm^2. one side of the rectangle is x cm. express the perimeter of the rectangle in terms of x and show that this rectangle cannot have a perimeter of 12 cm. the perimeter of the rectangle in terms of x is __ cm