319. $\sqrt{5-x}+2=7$.

319. $\sqrt{5-x}+2=7$. 

The equation is already in English, so no translation was needed for the mathematical expression. However, if you meant to have the problem solved, here is the solution:

To solve the equation $\sqrt{5-x}+2=7$, we first isolate the square root term:

1. Subtract 2 from both sides:
   \[
   \sqrt{5-x} = 5
   \]

2. Square both sides to eliminate the square root:
   \[
   5-x = 25
   \]

3. Solve for \( x \):
   \[
   -x = 25 - 5
   \]
   \[
   -x = 20
   \]
   \[
   x = -20
   \]

So, the solution is \( x = -20 \).
Solution. Isolate the radical and square both sides of the equation:

$$
\sqrt{5-x}=7-2 ;(\sqrt{5-x})^{2}=5^{2} ; 5-x=25 ;-x=20 ; x=-20
$$

Perform the check: $\sqrt{5-(-20)}+2=7 ; \sqrt{2} 5+2=7 ; 5+2=7$. Therefore, $x=-20$ is the solution to the equation.