Question

How do you solve `10^(-x+4) +7 = 5` and find any extraneous solutions?

Answer 1

There is no real solution.

Explanation:

For `a > 0, a^n>0 and lim n to -oo` of `a^n = 0`.

So, `10^(-x+4)>0`. Here, it is valued as `-2`.