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

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Answer 1 · 2016-06-04T04:08:20

There is no real solution.

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 $-2$ .

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