Find the length of the sides of the original square

Question

If the sides of a square are increased by 3cm the area becomes 64cm² 

Answer 1

(X+3)^2 = 64
>adding three the side, then squaring gives you area of square

x+3 = 8
>taking square root is easier here because 64 has a perfect square root

x=5
>Isolate the variable
-I am wondering though, if you mean the perameter as a whole is increased by 3, rather than just each side being increased by 3, as I've done here..

Answer 2

X - side of the original square:

 

 

 

( X+3 )^2 = 64 

 

 

X^2 + 6X + 9 = 64

 

X^2 + 6X - 55 = 0

 

(X +11) ( X -5 ) = 0

 

 X = -11   X =5/ answer

 

Test :

( 5+3 ) ^2 = 64