Question

7^(-x-9)=4^(4x). solve for x using base 10.

Answer 1

7^(-x - 9) = 4^(4x)

(-x - 9)(log 7) = 4x(log 4)

-x log 7 - 9 log 7 = 8x log 2

x(8 log 2 + log 7) = -9 log 7

x = -(9 log 7)/(8 log 2 + log 7)