Answer: B) 6
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Explanation:
x = original side length
2x = double the side length
The old area is x^2. The new square area is (2x)^2 = 4x^2
new area = (old area) + 27
4x^2 = x^2 + 27
4x^2-x^2 = 27
3x^2 = 27
x^2 = 27/3
x^2 = 9
x = sqrt(9)
x = 3
The old original square has a side length of 3 units.
The new larger square has a side length of 2x = 2*3 = 6 units which is the final answer (choice B)
old area = 3^2 = 9
new area = 6^2 = 36
The jump from 9 to 36 is +27 to help confirm the answer.
