Math problem in the fifth grade of primary school: the side length of the square is increased by 5 meters, and the area is increased by 95 square meters. What was the area of the square? How to solve it by formula? It is known that if the side length of a square increases by 5, the area will increase by 95, so we can assume that the original side length is a, so is it understandable that (a+5)*(a+5)-a*a=95? So if you simplify this equation, it is 25+ 10a=95, and a=7.

Understand?