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.
A ) ( x - 3 )( x + 1 ) [ not perfect ]
B ) ( x + 5 - √5 )( x + 5 + √5 ) [ n p ]
C ) ( x + 2 + 2√2 )( x + 2 - 2√2 ) [n p ]
D ) ( x - 6 )( x - 6 ) = ( x - 6 )^2 [ perfect ]
Thus the correct answer is option D .
I believe the answer is height
They are supplementary angles. They are located on a straight line, and when added together they will add up to 180 degrees.