Question

A square with side 3cm has the same perimeter as a rectangle 5cm long find the difference in they areas

Answer 1

All sides of a square are the same, add all the sides up for a perimeter of 12 (3 + 3 + 3 + 3=12). a rectangle that’s 5cm long will have another side that is also 5cm long, so add those and you’ll get 10. to achieve the same perimeter, you’d need to add 2, which means the other two sides are 1cm (10 + 1 + 1 = 12). you multiply the length and the width of both shapes to get their areas.
square: 3 x 3 = 9
rectangle: 5 x 1 = 5
then, subtract the areas from each other.
9 - 5 = 4
the difference in their areas is 4.