Square a is 40 square centimeters larger than square B. find the area of square a and B. the sum of the sides of square a and B is 20 cm,

Square a is 40 square centimeters larger than square B. find the area of square a and B. the sum of the sides of square a and B is 20 cm,

Suppose that the length of side a is x cm and that of side B is 20-x cm
x²-(20-x)²=40
x²-(400-40x+x²)=40
40x-400=40
40x=440
x=11
The area of a: 11 × 11 = 121 square centimeters
Area of B: 121-40 = 81 square centimeters