What does x equal if $log(7x)=2$ ?

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Answer 1 · 2018-05-17T18:10:54

$x=100/7$

$log7x=2$

But $2=log100$ (because $10^2=100$ ) hence

$log7x=log100$

By inyectivity of log function we can say that $7x=100$

$x=100/7$

This a valid solution because $log(7·100/7)=log100=2$

Answer 2 · 2018-05-17T18:50:36

$x=100/7$

We have $log_10(7x)=2$

which can be rewritten as

$10^2=7x$

$=>100=7x$

Dividing both sides by $7$ , we get

$x=100/7$

Hope this helps!

What does x equal if log(7x)=2log(7x)=2?