Can someone please help me with this ty!!

6.3x+14 and 1.5x-6 answer in simplified form

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

The formula to determine energy is e=1/2mv2? what is the formula solved for v?