120 is the right answer that is what my teacher told me
Answer:

Step-by-step explanation:
The domain of a function is all of the values that
can be under that specific function. In this case, we're asking what values of
allow
to exist.
In order for square roots to exist, the quantity under the square root must be greater than or equal to
, because you can't take the square root of a negative number. Therefore, we can write the following inequality to solve for
:

Solving this inequality, we get:

(Subtract
from both sides of the inequality to isolate
)
(Multiply both sides of the inequality by
to get rid of
's coefficient)
Hope this helps!
Answer:

Step-by-step explanation:
Use
for the equation of a circle in standard form with radius
and center
. Therefore, the equation of the circle in standard form is 