What is the sum of all natural numbers $x$ that satisfy the exponential inequality $\left( \frac { 1 } { 5 } \right) ^ { 1 - 2 x } \leq 5 ^ { x + 4 }$? [4 points] (1) 11 (2) 12 (3) 13 (4) 14 (5) 15
What is the sum of all natural numbers $x$ that satisfy the exponential inequality $\left( \frac { 1 } { 5 } \right) ^ { 1 - 2 x } \leq 5 ^ { x + 4 }$? [4 points]\\
(1) 11\\
(2) 12\\
(3) 13\\
(4) 14\\
(5) 15