SAT Math Practice Exam

Answer D: A square is a rectangle whose all sides are equal. Its area is equal to square of its sides.
Area= (side)²
Diagonal x²=2(side)²,
Area=x²/2.

Key takeaway: The word problems based on basic geometry are easy to tackle if you remember simple formulae (perimeter, area) of rectangle, square, circle etc. and their applications. Practice over relationships of length, width perimeter and area rectangle and square.