Answer:
[tex]7+\sqrt{x+3}[/tex]
Step-by-step explanation:
The conjugate of a radical expression is obtained by changing the sign of the middle term.
The conjugate of [tex]a+\sqrt{b}[/tex] is simply [tex]a-\sqrt{b}[/tex]
Therefore, to obtain the conjugate of the given expression we simply shall be changing the negative sign to positive;
The conjugate of [tex]7-\sqrt{x+3}[/tex] is simply;
[tex]7+\sqrt{x+3}[/tex]