Answer:
√7i = x
Step-by-step explanation:
x²+y²=9;
y² = 9-x²
y = √(9-x²)
As line is given by y= 4, the solution of the system is:
4 = √(9-x²)
16 = 9-x²
7 = -x²
-7 = x²
√-7 = x
As √-7 doen't exist, you should use i = √-1;
Thus,
√7i = x
I hope it helps!