564-?=199+197

To solve for the unknown value, let's first simplify the right side of the equation:

\[ 199 + 197 = 396. \]

Now we can rewrite the equation:

\[ 564 - ? = 396. \]

Next, we isolate the unknown value by rearranging the equation:

\[ ? = 564 - 396. \]

Now, perform the subtraction:

\[ 564 - 396 = 168. \]

So, the unknown value is:

\[ ? = 168. \]