Answer:
5 m
Explanation:
Set up an equation using the square area formula, A = s²
Let x represent the original side length:
(x + 3)² = 64
Simplify:
x² + 6x + 9 = 64
Subtract 64 from both sides:
x² + 6x - 55
Factor by finding 2 factors of -55 that add up to 6:
(x + 11)(x - 5) = 0
Solve for the 2 solutions:
x + 11 = 0
x = -11
x - 5 = 0
x = 5
The side length cannot be be negative, so the answer is 5.
The side length of the original square is 5 m.