Find all real numbers a that satisfy \frac{1}{64a^3 + 7} - 7 = 0.
1 / (64a^3 + 7) - 7 = 0
1 / (64a^3 + 7) = 7
1 = 7 (64a^3 + 7)
1 = 448a^3 + 49
-48 = 448a^3
-48 / 448 = a^3
-3/28 = a^3
a = (-3/28)^(1/3)
+2653 
