Question

Y=log x If y=10, then what is x?

Answer 1

Assuming we're working with the base 10 log, you can solve by making both sides exponents to a base of 10 (which cancels the log on the right side):

$10=log x \\ 10^{10}=10^{logx} \\ x = 10^{10}$

Answer 2

The answer:   x = 10¹⁰ = 10,000,000,000  ↔ (ten billion).
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Explanation:
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log x = y ↔ log₁₀ x = y ;  ↔  log₁₀ x = 10 ;   ↔  x = 10¹⁰ ;
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 →  x = 10¹⁰ = 10,000,000,000  ↔ (ten billion).
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