Anybody have a proper answer for this?

Asystem of equations has 1 solution. if 4x-y=5 is one of the equations , which could be the other equation ?

What is x3+3x2−16x−48 divided by x−1?

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