x + 7 - √(x - 4)
Replace x with 1.
1 + 7 - √(1 - 4)
1 + 7 - √(-3)
1 + 7 - i√3
8 - i√3 is your final answer.
You were very close.
When you have a negative number under a radical, you can multiply it by i to make it not a negative.
The simplified form of √-3 is i√3.
Your answer is 8 - i√3.
(Yes imaginary numbers exist :3)
