Need some help with these two problems. :)

2. Hint: Add 3 to both sides, then square both sides.

Subsituting 0 will get a complex number

1.) Here is an example

x=2 is has potential for extraneous roots because if you square both sides, and get x²=4, there are other possible solutions that DON'T solve the original equation.

Based on that, what do you think the answer is?

Solve for x:
sqrt(x^2 - 9) - 3 = 0

Isolate terms with x to the left hand side.
Add 3 to both sides:
sqrt(x^2 - 9) = 3

Eliminate the square root on the left hand side.
Raise both sides to the power of two:
x^2 - 9 = 9

Isolate terms with x to the left hand side.
Add 9 to both sides:
x^2 = 18

Eliminate the exponent on the left hand side.
Take the square root of both sides:

x = 3 sqrt(2)    or     x = -3 sqrt(2)