Question

What is the domain of the function y=2 sqrt x-5?

Answer 1

The domain is C, x >= 5.

Think about it, we can't square root a negative number, so A and B are automatically out of the question

If we put in x = 6, then we get sqrt(1), which is valid. So D is out.

Answer 2

`x\geq 5`

Explanation:

we have

`y=2√(x-5)`

we know that

The radicand (number under a radical) must be greater than or equal to zero

so

`x-5\geq 0`

solve for x

Adds
`5` both sides

`x\geq 5`

the domain is the interval---------> [5,∞)

All real numbers greater than or equal to
`5`