We have to find x given that 28^(4x-6)=1/784

28^(4x-6)=1/784

=> 28^(4x-6)=1/28^2

=> 28^(4x-6)=28^(-2)

As the base is the same, we equate the exponent

=> 4x - 6 = -2

=> 4x = 4

=> x = 1

**Therefore x = 1**

We have to find x given that 28^(4x-6)=1/784

28^(4x-6)=1/784

=> 28^(4x-6)=1/28^2

=> 28^(4x-6)=28^(-2)

As the base is the same, we equate the exponent

=> 4x - 6 = -2

=> 4x = 4

=> x = 1

**Therefore x = 1**