It is 3i.
The square root of -9 is the square root of -1 times the square root of 9.
So: the square root of 9 is 3, and the square root of -1 is called i (this doesn't actually exist, it's just imaginary).
Then, the square root of -9 is 3i.
112/2=56 (sum of both lengths)
4x=56
x=14
length=42
width=14
Answer:x=2
Step-by-step explanation:
-3x-9=-15
-3x=-6
x=2