When the side length of a square is increased by 6 cm, the area is increased by 114 square cm. How many cm is the original side length of a square?

When the side length of a square is increased by 6 cm, the area is increased by 114 square cm. How many cm is the original side length of a square?

(x+6)^2-x^2=114
x^2+12x+36-x^2=114
12x=78
x=6.5
The original side length of the square is 6.5cm