Which choice is the conjugate of the expression below when [tex]x \geq -4[/tex]?

[tex]5 - \sqrt{x + 4}[/tex]

A. [tex]5 + \sqrt{x + 4}[/tex]
B. [tex]5 - \sqrt{x + 4}[/tex]
C. [tex]5 + \sqrt{x - 4}[/tex]
D. [tex]5 - \sqrt{x - 4}[/tex]



Answer :

To determine which choice is the conjugate of the expression [tex]\( 5 - \sqrt{x + 4} \)[/tex], let's first recall what a conjugate is in the context of radical expressions.

The conjugate of an expression that includes a square root is typically formed by changing the sign of the term with the square root. In this case, the term with the square root in the given expression [tex]\( 5 - \sqrt{x + 4} \)[/tex] is [tex]\( -\sqrt{x + 4} \)[/tex].

Following this rule, the conjugate of [tex]\( 5 - \sqrt{x + 4} \)[/tex] can be found by changing the sign before the square root term, giving us:

[tex]\[ 5 + \sqrt{x + 4} \][/tex]

Now let's compare this result with the provided choices:

- A. [tex]\( 5 + \sqrt{x + 4} \)[/tex]
- B. [tex]\( 5 - \sqrt{x + 4} \)[/tex]
- C. [tex]\( 5 + \sqrt{x - 4} \)[/tex]
- D. [tex]\( 5 - \sqrt{x - 4} \)[/tex]

The correct conjugate of the expression [tex]\( 5 - \sqrt{x + 4} \)[/tex] is:

[tex]\[ 5 + \sqrt{x + 4} \][/tex]

So, the correct choice is:

[tex]\[ \boxed{A} \][/tex]