Which three lengths can NOT be the lengths of the sides of a triangle? 21 m, 6 m, 10 m 21 m, 6 m, 10 m 11 m, 11 m, 12 m 11 m, 11 m, 12 m 23 m, 17 m, 14 m 23 m, 17 m, 14 m 5 m, 7 m, 8 m

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