Answer:
The side length is multiplied by the scale factor of 3, which makes it 49.5
Explanation:
The scale factor goes as follows
length : scale factor
area: scale factor squared
Volume : scale factor cubed
Since we increased the area by 9, that would be the scale factor squared
Take the square root of 9, which is 3, and that is the scale factor
We want to know what happens to the length
It is multiplied by the scale factor
16.5*3 = 49.5