Find all real fourth roots of 16

Arectangular exercise mat has a perimeter of 36 feet the length of the mat is twich the width writeand solve an equation to determine the length in feet. of the mat then find the area in square feet of the mart

If the sales price of a dvd is $20 and the markup is 34%, what is the cost of the dvd?

The perimeter of a rectangle is 42 inches. if the width of the rectangle is 6 inches, what is the length