To find the dimensions of a rectangle given its area, we factor the algebraic expression representing the area. The context shows that factoring an area expression reveals its dimensions, and it reviews algebraic identities like (a-b)^2 = $a^{2}$ - 2ab + $b^{2}$. For part (i), the expression is a perfect square trinomial that factors into two identical binomials, meaning the rectangle is actually a square. For part (ii), the expression is a difference of two squares, which factors into the product of a sum and a difference of two terms.